Bioavailable polyamines

ABSTRACT

Disclosed herein are pharmaceutical salts of a cationic protonated polyamine pharmaceutical agent and an anionic organic carboxylate which is hydrophobic when in protonated form, particularly suited for oral administration, where these salts have good bioavailability in solid dosage forms and may be used in the treatment of cancer and other medical conditions for which the pharmaceutical agent is intended.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/753,291, filed Feb. 17, 2018, now U.S. Pat. No. 10,632,145, issuedApr. 28, 2020, which is a national phase application under 35 U.S.C. §371 of International Application No. PCT/US2017/023250, filed Mar. 20,2017, which claims the benefit under 35 U.S.C. § 119(e) of U.S.Provisional Patent Application No. 62/313,657 filed Mar. 25, 2016, whereeach application is incorporated herein by reference in its entirety forall purposes.

FIELD OF THE INVENTION

The present invention relates generally to pharmaceutical compositions,and more specifically to polyamines that are in a bioavailable form, andthe manufacture and use thereof.

BACKGROUND

Polyamines have demonstrated many useful biological properties and areunder study as active pharmaceutical agents for many medical conditions.See, e.g., Senanayake T. et al. Essay Biochem., 46:77-94 (2013); Zini M.et al. Chemico-Biological Interactions, 181:409-416 (2009); Kaur N. etal. J. Med. Chem., 51:2551-2560 (2008); Boncher, T. et al. Biochem. Soc.Trans., 35(2):356-363 (2007); Melchiorre C. et al. J. Med. Chem.,53:5906-5914 (2010); and Polyamine Drug Discovery, edited by PatrickWoster and Robert Casero, RCS Publishing, 2011,D01:10.1039/9781849733090.

For example, certain polyamines have been identified as inhibitors ofmonoamine oxidase A and B (MAO A and MAO B) and vascular adhesionprotein 1 (VAP-1), suggesting they may be useful inanti-neurodegenerative and anti-depressant therapies such as Parkinson'sand Alzheimer's diseases, and affective disorders. See, e.g., BonaiutoE. et al., Eur. J. Med. Chem., 70:88-101 (2013). For other reports ofthe neuroprotective effects of polyamines and/or their use in treatingmental and neurological disorders, see, e.g., Zhang X. et al. ActaPharmaceutica Sinica B, 5(1):67 73 (2015); Saiki R. et al. Bioorganic &Medicinal Chem. Letters, 23:3901-3904 (2013); Fiori L M et al. J.Psychiatry Neurosci., 33(2):102-110 (2008); and Gilad G M and Gilad V H,J. Pharmacology and Experimental Therapeutics, 291(1):39-43 (1999).

Cancer chemotherapy and chemoprevention is another utility for polyaminepharmaceuticals. See, e.g., Murray-Stewart T. et al. Amino Acids,46(3):585-594 (2014); Casero R A, Cancer Discovery, 975-977 (September2013); Minarini A. et al. European J. Medicinal Chem., 67:359-366(2013); Casero R A and Woster P M, J. Med. Chem., 52:4551-4573 (2009);Rossi T. et al. Anticancer Research, 28:2765-2768 (2008); Seiler N. andRaul F. J. Cell. Mol. Med. 9(3):623-642 (2005).

Polyamines are also under investigation as treatment for tropicaldiseases. See, e.g., Verlinden B K et al. Bioorganic & MedicinalChemistry, 23:5131-5143 (2015); and O'Sullivan M C et al. Bioorganic &Medicinal Chemistry, 23:996-1010 (2015).

The immunomodulatory effect of increased polyamine metabolism has beendetailed in many scientific reports. Several studies have demonstratedan immunological inhibitory effect of increased levels of polyaminessurrounding tumors. For example, Moulinoux and coworkers describedexperiments where a complete depletion of polyamine levels in micegrafted with 3LL (Lewis lung) carcinoma was accomplished by treatmentwith DFMO, a polyamine oxidase inhibitor and neomycin to prevent the gutmicrobial flora from providing polyamines. In these mice, tumor growthwas reduced and immune system abnormalities seen in tumor-bearinganimals were reversed. See, e.g., Chamaillard, L., et al. Polyaminedeprivation prevents the development of tumor-induced immunesuppression. British Journal of Cancer, 76:365-370 (1997). The decreasedspleen cell interleukin 2 (IL-2) production and CD4+ and CD8+ lymphocytepopulations observed prior to treatment with drugs were reversed andpreviously increased polyamine levels in the spleen were lowered. It wasnecessary to maintain a total blockage of all major polyamine sources tosee these reversals. The T-lymphocyte population restoration did notdepend upon the stage of tumor growth. No other vaccine activation ortumor-directing antigens were required.

Additionally, Moulinoux and coworkers examined the effects of more totalpolyamine depletion in mice grafted with 3LL carcinoma in relation tothe re-stimulation of the non-specific immune system specializing intumor cell killing. See, e.g., Chamaillard, L., et al. Polyaminedeprivation stimulates natural killer cell activity in cancerous mice.Anticancer Research, 13:1027-1033 (1993). The decrease in the cytotoxicactivity of the mouse's natural killer (NK) cells was reversed in thesepolyamine depleted animals. The authors conclude that polyamines,secreted by the tumor itself as well as absorbed through thegastrointestinal tract, can be considered not only as autocrine growthfactors but also as natural immunosuppressive factors.

Soda and coworkers studied the effects of polyamines on cellular immunefunction. See, e.g., Kano, Y., et al. Increased blood spermine levelsdecrease the cytotoxic activity of lymphokine-activated killer cells: anovel mechanism of cancer evasion, Cancer Immunology, Immunotherapy,56:771-781 (2007). Peripheral blood mononuclear cells (PBMCs) fromhealthy volunteers were cultured with spermine, spermidine or putrescineand the results on immune cell function were examined. Treatmentresulted in decreased adhesion of non-stimulated PBMCs to tissue cultureplastic in a dose- and time-dependent manner without affecting cellviability or activity. This decreased adhesion was also associated witha decrease in the number of CD11a positive and CD56 positive cells. In agroup of 25 cancer patients, changes in blood spermine levels aftersurgery were negatively correlated with changes in lymphokine-activatedkiller cells (LAK) cytotoxicity. These authors concluded that increasedblood spermine levels maybe an important factor in the suppression ofantitumor immune cell function.

A study reported by Bowlin noted the effect of the polyaminebiosynthesis inhibitor DFMO on immune system cell expression in normaland tumor-bearing (B16 melanoma) C57BL/6 mice. See, e.g., Bowlin, T. L.,et al. Effect of polyamine depletion in vivo byDL-alpha-difluoromethylornithine on functionally distinct populations oftumoricidal effector cells in normal and tumor-bearing mice. CancerResearch, 46:5494-5498 (1986). They observed that DFMO treatment ofthese immune competent mice for 6 days reduced splenic leukocytepolyamine levels and resulted in the induction of cytotoxicT-lymphocytes in both normal and tumor-bearing animals. While putrescineand spermidine levels were significantly reduced, spermine levels werenot. This led the authors to suggest that the generation of CTLs issensitive to spermine levels.

Another study by the same authors explored the effect of treatment byeach of three different ornithine decarboxylase inhibitors ontumoricidal macrophage activities in vivo. See, e.g., Bowlin, T. L., etal. Effects of three irreversible inhibitors of ornithine decarboxylaseon macrophage-mediated tumoricidal activity and antitumor activity inB16F1 tumor-bearing mice. Cancer Research 50:4510-4514 (1990).Tumor-bearing mice that were treated with 0.5 to 2.0% oral DFMO hadtwo-fold augmented macrophage mediated cytolysis of B16F1 cells ex vivo.An earlier study by Bowlin showed that polyamine oxidationdown-regulates IL-2 production by human peripheral blood mononuclearcells. See, e.g., Flescher, E., et al. Polyamine oxidationdown-regulates IL-2 production by human peripheral blood mononuclearcells. Journal of Immunology, 142:907-912 (1989).

Gensler reported studies exploring the ability of DFMO to prevent skincarcinogenesis and immunosuppression induced by ultraviolet irradiationin immuno-competent BALB/c mice. Gensler, H. L. Prevention byalpha-difluoromethylornithine of skin carcinogenesis andimmunosuppression induced by ultraviolet irradiation. Journal of CancerResearch and Clinical Oncology 117:345-350 (1991). Mice pretreated for 3weeks with 1% DFMO in their drinking water and then irradiated with UVBradiation had a reduced, 9% occurrence of skin cancer whereas theuntreated control group developed cancers in 38% of the mice. The degreeof removal of immunosuppression in the DFMO-treated mice was measured bya passive-transfer assay. Splenocytes from UV-irradiated mice whentransferred to naïve mice prevented their normal ability to rejectUV-induced tumor challenges (20 of 24 of mice grew tumors). When thesplenocytes from UV-irradiated mice that where treated with DFMO weretransferred to naïve mice, the majority of tumors were rejected (only 2of 24 grew).

Gervais reported experiments looking at the phenotype and functionalactivity of dendritic cells from cancer patients and investigated theeffect of putrescine on these immune cells. See, e.g., Gervais, A., etal. Dendritic cells are defective in breast cancer patients: a potentialrole for polyamine in this immunodeficiency. Breast Cancer Res.,7:R326-335 (2005). Cells from cancer patients yielded a lower yield ofdendritic cells and these cells showed a weaker expression of MHC classII molecules. By adding putrescine to dendritic cells from normaldonors, it was possible to reduce the final cytolytic activity oflymphocytes, mimicking the defective dendritic cell function of cancerpatients.

Evans observed that spermine suppresses the sensitivity of cervicalcarcinoma cells to cytotoxic LAK lymphocytes collected from more thanhalf the human subjects studied. See, e.g., Evans, et al.Spermine-directed immunosuppression of cervical carcinoma cellsensitivity to a majority of lymphokine-activated killer lymphocytecytotoxicity. Nat. Immun., 14:157-163 (1995).

Tracey has reported that spermine has an immune inhibitory effect. See,e.g., Zhang, M., et al. Spermine inhibits pro-inflammatory cytokinesynthesis in human mononuclear cells: a counterregulatory mechanism thatrestrains the immune response. J Exp. Med., 185:1759-1768 (1997).Specifically, Tracey observed that LPS stimulation of monocytes causesan increase in the uptake of spermine by the polyamine transportapparatus of the cell. They used a polyamine transport inhibitor,4-bis(3-aminopropyl)-piperazine (BAP) to block the inhibitory activityof spermine on monocyte TNF production.

Experiments using carrageenan-induced inflammation in rats showed BAPenhanced the production of TNFα and increased the resulting edema in thefoot pad. See, e.g., Zhang, M., et al. Spermine inhibition of monocyteactivation and inflammation. Mol. Med., 5:595-605 (1999). See alsoGervais, A., et al. Ex vivo expansion of antitumor cytotoxic lymphocyteswith tumor-associated antigen-loaded dendritic cells. AnticancerResearch 25, 2177-2185 (2005) and Susskind, B. M. & Chandrasekaran, J.Inhibition of cytolytic T lymphocyte maturation with ornithine,arginine, and putrescine. Journal of Immunology, 139:905-912 (1987).

Szabo and colleagues reported studies exploring the mechanism of theinhibitory effect of polyamines on the induction of nitric oxidesynthase (NOS). See, e.g., Szabo, C., et al. The mechanism of theinhibitory effect of polyamines on the induction of nitric oxidesynthase: role of aldehyde metabolites. Br. J. Pharmacol., 113:757-766(1994).

The NO produced by the enzyme iNOS is a central effector molecule in theinnate immune response to pathogens and is the focus of many groupsworking towards understanding the role of the microbe H. pylori plays inthe pathogenesis of stomach ulcers and gastric cancer. Casero and Wilsonobserved that spermine may inhibit the production of themacrophage-derived NO coming from the inducible NO synthase (iNOS). See,e.g., Bussiere, F. I., et al. Spermine causes loss of innate immuneresponse to Helicobacter pylori by inhibition of inducible nitric-oxidesynthase translation. The Journal of Biological Chemistry 280:2409-2412(2005) and Chaturvedi, R., et al. Induction of polyamine oxidase 1 byHelicobacter pylori causes macrophage apoptosis by hydrogen peroxiderelease and mitochondrial membrane depolarization. The Journal ofBiological Chemistry, 279:40161-40173 (2004).

A review article by Soda provides an overview of the immunosuppressiverole played by increased polyamine metabolism. See, e.g., Soda, K. Themechanisms by which polyamines accelerate tumor spread. J. Exp. Clin.Cancer Res., 30:95 (2011). However, despite the promise of polyaminepharmaceutical agents, not all reported experiments demonstrate goodclinical efficacy for these agents.

N1,N11-diethylnorspermine (DENSpm; DENSPM) was clinically evaluated fortherapeutic effect against previously treated metastatic breast cancer,see e.g. Wolff, et al. Clinical Cancer Res., 9:5922-5928 (2003). In thisstudy, DENSpm was delivered as its free base by intravenous infusionsover a 15 minute period. Treatment cycles involved injections of 100mg/m²/day over 5 days every 21 days. A short plasma half-life of 0.5 to3.7 h was observed. An additional report using DENSpm i.v. infusions fornon-small cell lung cancer treatment also failed to demonstrate clinicalbenefits (Hahm, H. A. el al Clinical Cancer Res., 8:684-690 (2002)).

N1,N14-diethylhomospermine (DEHSpm; DEHSPM) is an additionalbis-ethylated polyamine analog tested for clinical efficacy in humanoncology trials. Twice daily, subcutaneous injections of this agent asits tetrahydrochloride salt at 12.5, 25 and 37.5 mg/kg in solid tumorpatients showed peak drug levels at 15 to 30 minutes after injection.The drug was not observed in plasma of treated patients 2-4 hrs.post-injection (Wilding, G. et al. Investigational New Drugs, 22:131-138(2004)). None of the 15 patients were found to have an objectiveresponse and significant toxicities at the highest dose limited furtherevaluation in cancer patients.

Squalamine is a chemically synthesized aminosterol, originally isolatedfrom the liver of the dogfish shark. Studies in tumor-bearing mice haveshown that squalamine acts as an inhibitor of angiogenesis and showsactivity against several models of cancer in mice including lung,breast, ovarian and prostate. Clinical testing of squalamine, as itslactate salt, against advanced non-small cell lung cancer has beenreported (Herbst, R. S. Clinical Cancer Res., 9:4108-4115 (2003)).Limited clinical activity was observed in this testing, where squalaminewas delivered by continuous i.v. infusions over 3 h at dose levels of100 to 400 mg/m²/day. Plasma half-life of squalamine was measured to bebetween 1 and 2 h. An earlier report on the clinical testing ofsqualamine lactate salt used 120 h continuous i.v. infusion as thedelivery method (Bhargava, P. et al. Clinical Cancer Res. 7:3912-3919(2001)).

Deoxyspergualin is a synthetic analog of the bacteria derived sperqualinand has strong immunomodulatory effects on lymphocytes, macrophages andneutrophils. It is approved for treatment of steroid-resistanttransplant rejection in Japan. It is delivered by subcutaneousinjections at 0.5 mg/kg/day for up to 21 days. The pharmacokineticbehavior of deoxyspergualin delivery by 3 h intravenous infusions hasbeen reported (Dhingra, K. et al Cancer Research, 55:3060-3067 (1995))and showed a very short half-life of 1.8 h.

F14512 is a polyamine-epipodophyllotoxin conjugate that is able totarget cancer cells with high polyamine transporter activity(Kruczynski, A. et al Leukemia 27:2139-2148 (2013)). It is beingdeveloped for use against AML and solid tumors and a recent publicationshowing its development against canine tumor showed it is delivered byi.v. injections (Tierny, D. Clinical Cancer Res., 21(23):5314-5323(2015)). Plasma levels of F14512 in dogs treated with 0.05, 0.060,0.070, 0.075 and 0.085 mg/kg by intravenous 3 hr. infusions increasedwith dose and were estimated to be within therapeutic range atapproximately 2 to 3 hrs. for most dogs.

Mozobil is a bicyclam polyamine-containing drug approved for stem cellmobilization prior to hematopoeitic progenitor cell transplants duringcancer chemotherapy (De Clercq, E. Pharmacology and Therapeutics,128:509-518 (2010)). This drug is administered by subcutaneousinjection. Subcutaneous delivery to heathy volunteer patients at 40, 80,160, 240 and 360 μg/kg showed dose proportional pharmacokinetics andclearance by 10 hrs. Plasma half-life of Mozobil is 3 hrs. (Lack, N. A.,et al. Clin. Pharmacol. Ther., 77:427-436 (2005)).

Trientine is a polyamine analog approved for use in Wilson's disease.This polyamine analog acts as a copper chelating agent, aiding in theelimination of excess copper associated with Wilson's disease. AlthoughTrientine is delivered orally, as its hydrochloride salt in the clinic,its oral bioavailability is poor (8 to 30%). It has a relatively shorthalf-life in humans (2 to 4 h). A review covering the preclinical andclinical applications of Trientine has been published. See Lu, J.Triethylenetetramine pharmacology and its clinical applications.Molecular Cancer Therapeutics, 9:2458-2467 (2010).

Methylglyoxal bis(guanylhydrazone), also known as1,1′[methylethanediylidene]dinitrilodiguanidine and often abbreviated asMGBG, is a polyamine that functions as a competitive polyamine inhibitorof 2-adenosyl methionine decarboxylase (AMD-1), which catalyzes thesynthesis of spermidine. It is described as useful in, e.g., thetreatment of pain, such as inflammatory pain. See U.S. Pat. Nos.8,258,186 and 8,609,734.

Oral delivery of spermidine has recently been shown to improve hearthealth and longevity of mice (Eisenburg, T. et al. Nature Medicine,22(12):1428-1438 (2016)). Spermidine provided in the diet of miceenhanced cardiac autophagy, mitophagy and mitochondrial respiration andimproved the mechano-elastical properties of cardiomyocytes in vivo. Theauthors attributed the spermidine extension of lifespan of mice to theautophagy inducing activities of spermidine (Eisenburg, T. et al.Autophagy, 13(4):1-3 (2017)).

Lipinski devised a set of parameters that could predict the ability ofchemical substances to be orally bioavailable (Lipinski C A, et al. Adv.Drug Deliv. Rev., 46(1-3):3-26 (2001)). Known in the art as ‘The Rule of5’ these parameters were based on the molecule's chemical structure andincluded the number of hydrogen bond donors, hydrogen bond acceptors,molecular weight and lipophilicity measurements. Many exceptions tothese rules have been found and these parameters are now considered moreof a guidance used to predict a molecule's oral bioavailability.

While polyamines have desirable biological properties, the inventor(s)consider that their limited oral bioavailability remains an unsolvedhurdle in an effort to bring these materials to practical therapeuticuse. In particular, the bioavailability of polyamines by oraladministration has been a problem. Surprisingly, oral delivery ofpolyamine drugs as salts with hydrophobic carboxylic acids greatlyimproves their bio availabilities. Thus, there exists a need for apharmaceutical composition that can deliver polyamines and protonatedforms thereof to a patient in need, and which overcome one or more ofthe shortcoming associated with the prior art.

All of the subject matter discussed in the Background section is notnecessarily prior art and should not be assumed to be prior art merelyas a result of its discussion in the Background section. Along theselines, any recognition of problems in the prior art discussed in theBackground section or associated with such subject matter should not betreated as prior art unless expressly stated to be prior art. Instead,the discussion of any subject matter in the Background section should betreated as part of the inventor's approach to the particular problem,which in and of itself may also be inventive.

SUMMARY

The present invention relates to salts between protonated polyaminepharmaceutical agents (PPA) and deprotonated hydrophobic carboxylicacids (HCA). For example, in one embodiment the present disclosureprovides a salt of a cationic protonated polyamine pharmaceutical agentand an anionic hydrophobic carboxylate, wherein (a) the anionichydrophobic carboxylate is a carboxylate form of a hydrophobiccarboxylic acid as described herein, e.g., a fatty acid selected fromC₈-C₁₈ fatty acids; (b) the cationic protonated polyamine pharmaceuticalagent is a protonated form of a therapeutically effective polyamine suchas are described herein, for example, polyamines having from 2 to 4amine groups that are independently protonatable in water, andoptionally excluding peptides and proteins; and (c) and at least one ofthe protonatable amine groups of the polyamine is protonated to providethe cationic protonated polyamine pharmaceutical agent.

Optionally, the salts of the present disclosure may be characterized byone or more (two, three, four, etc.) additional features such asdisclosed in embodiments herein, including one or more of the followingfeatures. The salt may have two moles of anionic hydrophobic carboxylatefor each one mole of cationic protonated polyamine pharmaceutical agent,which may be named a PPA(HCA)₂ or PPA:(HCA)₂ salt. The cationicprotonated polyamine pharmaceutical agent may be a protonated form of apolyamine of formula (1). The anionic hydrophobic carboxylate may be acarboxylate form of a fatty acid selected from C₈-C₁₄ fatty acids. Thecationic protonated polyamine pharmaceutical agent may be adi-protonated form of a polyamine of formula AMXT 1501 and the anionichydrophobic carboxylate is deprotonated capric acid, and the salt hastwo moles of deprotonated capric acid for each one mole of protonatedAMXT 1501, so as to provide the dicaprate salt of AMXT 1501, optionallydenoted as AMXT 1501:(caprate)₂. The salt may be essentially pure, e.g.,it is not in admixture with more than 5 wt % of any other solid orliquid chemical. The salt may be a pharmaceutically active salt.

The present disclosure also provides, for example, methods for producingPPA-HCA salts, methods of formulating the salts into a pharmaceuticalcomposition or a precursor thereof, solid dosage forms of these salts,methods of administrating the salts to a subject in need thereof, andother compositions that include a salt of the present disclosure as acomponent. For example, the present disclosure provides pharmaceuticalcompositions that contain a PPA:HCA salt as described herein. Thepharmaceutical composition may be in a form as described herein, e.g., asolid form for oral dosage, i.e., a solid oral dosage form such as apill or tablet.

Thus, the present disclosure provides methods for producing PPA-HCAsalts. For example, in one embodiment the present disclosure provides amethod comprising: combining a polyamine, a hydrophobic carboxylic acidand a solvent so as to provide a solution; and thereafter isolating asolid residue from the solution, wherein the residue comprises a PPA-HCAsalt formed between the polyamine and the hydrophobic carboxylic acid.Optionally, the method may be further characterized by any one or more(e.g., any two, any three, any four) of the following: the polyamine isany of the pharmaceutically active polyamines identified herein; thehydrophobic carboxylic acid is any of the hydrophobic carboxylic acidsidentified herein; each of the polyamine and the hydrophobic carboxylicacid is at least 90% or at least 95% pure on a weight basis; about 1.0mole, e.g., 0.9-1.1 moles of hydrophobic carboxylic acid are combinedwith each 1.0 mole of polyamine, or about 2.0 moles, e.g., 1.8-2.2 molesof hydrophobic carboxylic acid are combined with each 1.0 mole ofpolyamine, or about 3.0 moles, e.g., 2.7-3.3 moles of hydrophobiccarboxylic acid are combined with each 1.0 mole of polyamine, or about4.0 moles, e.g., 3.6-4.4 moles of hydrophobic carboxylic acid arecombined with each 1.0 mole of polyamine; the solvent is selected from apure polar protic solvent and a mixture of solvents comprising a polarprotic solvent; the solvent comprises water, e.g., a water selected fromdeionized water and distilled water; the solvent comprises methanol; thepolyamine and the hydrophobic carboxylic acid are added to the solventso as to provide the solution; the method is performed in a batchprocess; the solvent is removed from the solution by a process selectedfrom evaporation and distillation, so as to isolate the residue from thesolution, or a co-solvent (an example being acetonitrile (ACN)) is addedto the solution so as to form a supernatant and the residue in the formof a precipitate, and wherein the supernatant is separated from theresidue so as to isolate the residue from the solution, or the solutionis chilled so as to form a supernatant and the residue in the form of aprecipitate, and wherein the supernatant is separated from the residueso as to isolate the residue from the solution; the polyamine, thehydrophobic carboxylic acid and the solvent are combined so as toprovide a clear solution; the polyamine, the hydrophobic carboxylic acidand the solvent are combined at a temperature within the range of 10-30°C.; the residue comprises at least 50%, or at least 95%, or at least 99%by weight of the salt; the method further comprises combining theresidue or a portion thereof with additional components so as to form apharmaceutical composition suitable for ingestion, e.g., the methodfurther comprises forming a solid dosage form selected from a pill, atablet, a capsule, a lozenge, a caplet, and a pastille, from the residueor a portion thereof. Additionally, continuous flow techniques could beused for the production and isolation of the PPA:HCA salt formsdescribed. Use of available flow apparatus, wherein solutions of thepolyamine free base, in a suitable solvent such as methanol, are mixedwith a co-solvent in which the salt is not soluble, such asacetonitrile, in a flow cell apparatus, allowing the continuousproduction of the insoluble, or soluble form of the PPA:HCA salt.

In addition, the present disclosure provides for the therapeutic use ofthe PPA:HCA salts. For example, the present disclosure provides a methodof treating cancer comprising administering to a subject in need thereofa therapeutically effective amount of a PPA:HCA salt. Optionally, thetherapeutically effective amount of the salt is administered to thesubject as a solid dosage form.

In addition, the present disclosure provides PPA:HCA salts as disclosedherein for use in medicine, or for use as a medicament, or for use inmanufacturing a medicament. For example, the present disclosure providessalts of the PPA AMXT 1501, where the HCA component is derived from aC₈₋₁₄ fatty acid or a C₁₀₋₁₂ fatty acid such as decanoic acid, alsoknown as capric acid, for use in medicine, e.g., for use as amedicament. Furthermore, the present disclosure provides PPA:HCA saltsas disclosed herein for use in the treatment of cancer. Thus, thepresent disclosure provides PPA:(HCA)₁, PPA:(HCA)₂ and PPA:(HCA)₃ salts,including salts wherein the PPA is known as AMXT 1501, and wherein theHCA component is derived from a fatty acid, e.g., C₈₋₁₄ or C₁₀₋₁₂ fattyacids such as capric acid, including the use of those salts in thetreatment of cancer. In one embodiment, the present disclosure providesPPA:(HCA)₂ salts, wherein the PPA is known as AMXT 1501, and wherein theHCA component is capric acid, including the use of that salt in thetreatment of cancer

This Brief Summary has been provided to introduce certain concepts in asimplified form that are further described in detail below in theDetailed Description. Except where otherwise expressly stated, thisBrief Summary is not intended to identify key or essential features ofthe claimed subject matter, nor is it intended to limit the scope of theclaimed subject matter.

The details of one or more embodiments are set forth in the descriptionbelow. The features illustrated or described in connection with oneexemplary embodiment may be combined with the features of otherembodiments. Thus, any of the various embodiments described herein canbe combined to provide further embodiments. Embodiments of theembodiments can be modified, if necessary to employ concepts of thevarious patents, applications and publications as identified herein toprovide yet further embodiments. Other features, objects and advantageswill be apparent from the description, the drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary features of the present disclosure, its nature and variousadvantages will be apparent from the accompanying drawings and thefollowing detailed description of various embodiments. Non-limiting andnon-exhaustive embodiments are described with reference to theaccompanying drawings. One or more embodiments are described hereinafterwith reference to the accompanying drawings in which:

FIG. 1 shows the chemical structures of some exemplary pharmaceuticallyactive polyamines (PPA in neutral form).

FIG. 2 shows a DSC scan for AMXT 1501 dicaprate, a salt of the presentdisclosure.

FIG. 3 shows a TGA scan for AMXT 1501 dicaprate, a salt of the presentdisclosure.

FIGS. 4A, 4B, 4C and 4D show individual animal plasma levels of AMXT1501 following single oral dosing of AMXT 1501 free base (FIG. 4A) andvarious salt forms of AMXT 1501 (FIGS. 4B (Dicholate), 4C (Phosphate)and 4D (Dicaprate)) to dogs.

FIGS. 5A, 5B, 5C and 5D shows average plasma levels of AMXT 1501following single oral dosing of groupings of dogs where either AMXT 1501free base or various salt forms of AMXT 1501 (FIGS. 5B (Dicholate), 5C(Phosphate) and 5D (Dicaprate)) were dosed once by oral delivery.

FIGS. 6A, 6B, 6C and 6D show individual animal AMXT 1501 plasmaconcentrations (ng/mL) following a single PO dose of AMXT 1501 dicaprate(8, 16 and 32 mg/kg/day and 16 mg/kg/day with 200 mg/kg/day DFMO) tomale and female beagle dogs at day 1, according to a study as describedherein.

FIGS. 7A, 7B, 7C and 7D show individual animal AMXT 1501 plasmaconcentration (ng/mL) following repeat once daily PO dosing of AMXT 1501dicaprate (8, 16 and 32 mg/kg/day and 16 mg/kg/day with 200 mg/kg/dayDFMO) to male and female beagle dogs at day 5, according to a study asdescribed herein.

FIGS. 8A and 8B show mean (±SD) AMXT 1501 plasma concentrations (ng/mL)after single (Day 1; FIG. 8A) or repeat once daily (Day 5; FIG. 8B) POdosing of AMXT 1501 monotherapy of AMXT 1501 dicaprate (8, 16 and 32mg/kg/day) to male and female beagle dogs, according to a study asdescribed herein.

FIGS. 9A and 9B show mean (±SD) AMXT 1501 plasma concentrations (ng/mL)after single (Day 1; FIG. 9A) or repeat once daily (Day 5; FIG. 9B) POdosing of 16 mg/kg/day AMXT 1501 monotherapy versus in combination withDFMO (200 mg/kg/day) to male and female beagle dogs, according to astudy as described herein.

FIGS. 10A, 10B, 10C and 10D show mean (±SD) AMXT 1501 plasmaconcentrations (ng/mL) after single (Day 1) or Repeat Once Daily (Day 5)PO dosing of AMXT 1501 dicaprate (8, 16 and 32 mg/kg/day and 16mg/kg/day with 200 mg/kg/day DFMO) to male and female beagle dogs, Day 1versus Day 5, according to a study as described herein.

FIGS. 11A and 11B show mean (SD) AMXT 1501 Plasma Concentrations (ng/mL)Following Single (Day 1, FIG. 11A) or Repeat Oral Dosing (Day 28, FIG.11B) to Male and Female Beagle Dogs; AMXT 1501 Dicaprate Dose LevelComparison (80, 160 or 320 mg of AMXT 1501 dicaprate) without DFMO(Males and Females Combined), according to a study as described herein.

FIGS. 12A, 12B, 12C, 12D, 12E and 12F show mean (SD) AMXT 1501 PlasmaConcentrations (ng/mL) Following Single (Day 1) or Repeat Oral Dosing(Day 28) to Male and Female Beagle Dogs; Males versus Females. FIG. 12Ashows data for Group 2 (low dose, 80 mg dose), Day 1. FIG. 12B showsdata for Group 3 (mid dose, 160 mg dose), Day 1. FIG. 12C shows data forGroup 4 (high dose, 320 mg dose), Day 1. FIG. 12D shows data for Group 2(low dose, 80 mg dose), Day 28. FIG. 12E shows data for Group 3 (middose, 160 mg dose), Day 28. FIG. 12F shows data for Group 4 (high dose,320 mg dose), Day 28, according to a study as described herein.

FIGS. 13A, 13B, 13C and 13D show dose-proportionality of oral deliveryof AMXT 1501 dicaprate enterically-coated tablets to beagle dogs.

DETAILED DESCRIPTION

Clinical evaluation of polyamines and polyamine analogs has beenhampered by delivery difficulties associated with their polycationicnature. Limitations with their oral bioavailability have resulted intheir preclinical and clinical evaluation using less than desirableintravenous or intraperitoneal injection methods. These deliverymethods, while sufficient for early preclinical evaluation in animalmodels, are unsatisfactory for eventual pharmaceutical development.Importantly, intravenous or intraperitoneal injections of polyamineanalogs tend to exacerbate their toxic side-effects. High plasmaconcentrations of these polycationic agents lead to deleterious actionsdue to the agents' physical and chemical properties. Intravenous orintraperitoneal injections lead to high initial plasma concentrationsfollowed by normal elimination. For many pharmacological targets inmammalian systems, delivery methods that lead to moderate, sustainedplasma levels of drug agents are highly desirable. For this reason, oraldelivery, with a delayed and sustained plasma exposure to the agent ispreferred. It is also highly desirable that each patient absorb the sameamount of drug based on a given dosage of drug being administered. Inother words, although two patients may be administered the same dose ofdrug, the drug may not be equally bioavailable for the two patients, dueto, e.g., differences in patient composition. A desirable component ofbioavailability is that subjects receiving the same dose of a drug alsoachieve the same or similar plasma concentrations of the activeingredient(s) in the drug. The present disclosure recognizes andaddresses these issues.

Briefly stated, in one embodiment the present disclosure relates tosalts, and more particularly to salts comprising a first molecule havingan ammonium group and a second molecule having a carboxylate group. Theammonium group of the first molecule is selected from the protonatedforms of primary, secondary and tertiary amines, i.e., ammonium groupshaving 3, 2 or 1 hydrogen atom(s) attached to the nitrogen atom of theammonium group, respectively. The first molecule may be referred to as aprotonated polyamine (PPA), which denotes that it contains two or moreamine groups, where each of the amine groups may be in a protonated orunprotonated form, although at least one of the amine groups is in aprotonated form so as the provide the ammonium group necessary to formthe salt. The first molecule is organic and biologically active, e.g.,it may be an organic pharmaceutical agent or organic activepharmaceutical ingredient (API) in a formulation. The second molecule islikewise organic, and in one embodiment is a small molecule. The secondmolecule is hydrophobic, which means that the second molecule is formed,at least in part, from a plurality of carbon atoms bonded to hydrogenatoms, and that an uncharged form of the second molecule is not solublein water. For convenience, the second molecule may be referred to hereinas a hydrophobic carboxylic acid (HCA).

Thus, in one embodiment, the present disclosure is directed to thecombination of a polyamine pharmaceutical agent and a hydrophobiccarboxylic acid such as a fatty acid. In another embodiment, the presentdisclosure is directed to the preparation of salts of the presentdisclosure. In another embodiment, the present disclosure is directed tothe administration of a salt formed between a polyamine pharmaceuticalagent and a hydrophobic carboxylic acid, such as a fatty acid, to asubject in need thereof, to achieve a therapeutic result. In anadditional embodiment, the present invention relates to the surprisinglyincreased bioavailability of polyamine drugs when delivered as saltsassociated with hydrophobic carboxylic acids. Prior to setting forththis disclosure in more detail, it may be helpful to an understandingthereof to provide definitions of certain terms to be used herein.Additional definitions are set forth throughout this disclosure. Thatis, the present disclosure may be understood more readily by referenceto the following detailed description of preferred embodiments of theinvention and the Examples included herein.

The term “salt” has its standard meaning in the art, and refers to apositively charged species (cation) and a negatively charged species(anion) that are complexed to one another through an ionic interaction.Generally, these salts do not involve covalent bonding between partnermolecular components. The salt possesses different biological andpharmacological properties compared to its component cationic andanionic species delivered separately. The term salt also refers to allsolvates, for example, hydrates of a parent salt compound. Salts can beobtained by customary methods known to those skilled in the art, forexample, by combining a compound with an inorganic or organic acid orbase in a solvent or diluent, or from other salts by cation exchange oranion exchange.

“Treatment,” “treating” or “ameliorating” refers to medical managementof a disease, disorder, or condition of a subject (i.e., patient), whichmay be therapeutic, prophylactic/preventative, or a combinationtreatment thereof. A treatment may improve or decrease the severity atleast one symptom of a disease, delay worsening or progression of adisease, delay or prevent onset of additional associated diseases, orimprove remodeling of lesions into functional (partially or fully)tissue.

A “therapeutically effective amount (or dose)” or “effective amount (ordose)” of a compound refers to that amount sufficient to result inamelioration of one or more symptoms of the disease being treated in astatistically significant manner. When referring to an individual activeingredient administered alone, a therapeutically effective dose refersto that ingredient alone. When referring to a combination, atherapeutically effective dose refers to combined amounts of the activeingredients that result in the therapeutic effect, whether administeredserially or simultaneously.

“Pharmaceutically acceptable” refers to molecular entities andcompositions that do not produce allergic or other serious adversereactions when administered to a subject using routes well-known in theart. The term, “pharmaceutically acceptable” is used to specify that anobject (for example a salt, dosage form, diluent or carrier) is suitablefor use in patients. An example list of pharmaceutically acceptablesalts can be found in the Handbook of Pharmaceutical Salts: Properties,Selection and Use, P. H. Stahl and C. G. Wermuth editors,Weinheim/Zurich:Wiley-VCHA/VHCA, 2002.

A “subject in need” refers to a subject at risk of, or suffering from, adisease, disorder or condition (e.g., cancer) that is amenable totreatment or amelioration with a compound or a composition thereofprovided herein. In certain embodiments, a subject in need is a mammal,e.g., a human. The subject may be warm-blooded animal such as mice,rats, horses, cattle, sheep, dogs, cats, monkeys, etc.

As mentioned above, an embodiment of the present disclosure relates tosalts that comprise positively charged first molecules and negativelycharged second molecules, each as defined herein. More particularly thesalt comprises a first molecule which is a protonated polyaminepharmaceutical agent (PPA), and a second molecule which is or comprisesa carboxylate group attached to a hydrophobic moiety (HCA). The termPPA:HCA as used herein refers to salts that comprise protonated PPA anddeprotonated HCA molecules, where the term PPA:HCA does not specify anyparticular stoichiometry between the PPA and HCA present in the salt,e.g., PPA:HCA refers broadly to all or any one of PPA:HCA salts having a1:1 PPA:HCA stoichiometry (also referred to as PPA:(HCA)₁), and saltshaving a 1:2 PPA:HCA stoichiometry (also referred to as PPA:(HCA)₂), andalso refers to salts having a 1:3 PPA:HCA stoichiometry (also referredto as PPA:(HCA)₃), as well as salts having a 1:4 PPA:HCA stoichiometry(also referred to as PPA:(HCA)₄), etc. depending on how manyprotonatable amine groups are present in the PPA and how manyequivalents of HCA are combined with the PPA. In one embodiment, PPA:HCAas used herein refers to salts of PPA:(HCA)₂ stoichiometry.

The salt may comprise more than one second molecule, e.g., twonegatively charged carboxylate molecules may each be complexed with asingle polyamine that has two positively charged sites. The salt maycomprise more than just the first and second molecules. For example, thesalt may be a solvate, in which case one or more solvent molecules arecomplexed to the salt. Also, the salt may comprise more than one anionicspecies, where that additional one or more anionic species may or maynot be a second molecule as defined herein. For example, the salt maycomprise a first molecule complexed with both a HCA as defined herein,and a second anionic species, e.g., chloride, which is not an HCA asdefined herein. For convenience, and unless otherwise specified, aprotonated position of a first molecule is necessarily associated with anegatively charged HCA as defined herein. Control of the production andcomposition of the PPA:HCA salts also enables formation of specificpolymorphs of the specified salts.

Protonated Polyamine Pharmaceutical Agent

The present disclosure provides salts that may be used to delivermolecules to a subject, where after their administration the salts mayundergo some change(s) in form, and it is this changed form thatactually exerts the desired biological effect. For example, the firstmolecule may be a pharmaceutically active compound in at least one of aprotonated or non-protonated form. In other words, although the firstmolecule is necessarily protonated in the salts of the presentdisclosure which are administered to the subject, the biologicallyactive form of the first molecule may or may not have the same amount ofprotonation as is present in the salt. As another example, the firstmolecule may be a pro-drug for the biologically active drug. Thus, thefirst molecule may undergo some changes in vivo, after administration,to generate the desired biologically active form. The first moleculewill be referred to herein as being pharmaceutically active, with theunderstanding that the desired biologically active form of the firstmolecule may not arise until after the salt formed from the firstmolecule is administered to a subject.

The first molecule may be a small molecule, which means it has amolecular weight of less than 10,000 g/mol, or in alternativeembodiments, of less than 9,000, or less than 8,000, or less than 7,000,or less than 6,000, or less than 5,000, or less than 4,000, or less than3,000, or less than 2,000, or less than 1,000 g/mol. Optionally, thefirst molecule excludes one or more of a peptide, polypeptide,poly(amino acid) and protein.

The first molecule comprises two or more ammonium groups, where anammonium group of the first molecule is selected from the protonatedforms of primary, secondary and tertiary amines, i.e., ammonium groupshaving 3, 2 or 1 hydrogen atom(s) attached to the nitrogen atom of theammonium group, respectively. The first molecule may be referred to as aprotonated polyamine (PPA), which denotes that it contains two or moreamine groups, where each of the amine groups may be in a protonated orunprotonated form, although at least one of the amine groups is in aprotonated form so as the provide the ammonium group necessary to form asalt complex with a HCA as disclosed herein. In one embodiment, thepolyamine comprises amine groups having a pKa/b of 6 to 13. Methods todetermine pKa values of the natural, and synthetic polyamines have beendescribed (Blagbrough, I. S.; Mewally, A. A.; Geall, A. J. Measurementof polyamine pKa values. Methods Mol. Biol. 2011, 720, 493-503). Theinfluence of protonation of the first amino group in a polyamine towardsthe pKa of the second amino group is well established in the scientificfield. Each protonated amine group thus lowers the pKa of the secondamino group. Therefore, formation of salts with monocarboxylic acids mayinvolve protonation of multiple amino groups of the polyamine, evenamino groups whose pKa values may be below 7.

In one embodiment, the first molecule has exactly two amine groups,where one or optionally both are in a protonated form. In oneembodiment, the first molecule has exactly three amine groups, whereone, or optionally two or all three are in a protonated form. In oneembodiment, the first molecule has exactly four amine groups, where one,or optionally two or three or all four are in a protonated form.

The first molecule is an organic molecule, meaning that it comprisescarbons and hydrogens. The first molecule may be a so-called smallmolecule, which means that it has a molecular weight of less than 2,000g/mol, or in alternative embodiments, of less than 1,500, or less than1,000, or less than 900, or less than 800, or less than 700, or lessthan 600, or less than, or less than 500 g/mol. Optionally, the firstmolecule is not a protein or polypeptide, and/or is not apolynucleotide.

In one embodiment, the PPA is a protonated form of a polyamine havingthe formula (I)

wherein

-   -   a, b, and c independently range from 1 to 10;    -   d and e independently range from 0 to 30;    -   each X is independently either a carbon (C) or sulfur (S) atom;    -   R₁ and R₂ are independently selected from H or from the group of        -   a straight or branched C₁₋₅₀ saturated or unsaturated            aliphatic, carboxyalkyl, carbalkoxyalkyl, or alkoxy;        -   a C₁₋₈ alicyclic;        -   a single or multiring aryl substituted or unsubstituted            aliphatic;        -   an aliphatic-substituted or unsubstituted single or            multiring aromatic;        -   a single or multiring heterocyclic;        -   a single or multiring heterocyclic aliphatic;        -   a C₁₋₁₀ alkyl;        -   an aryl sulfonyl;        -   or cyano; or        -   R₂X(O)_(n)— is replaced by H;            wherein * denotes a chiral carbon position; and            wherein if X is C then n is 1; if X is S then n is 2; and if            X is C then the XO group may be CH₂ such that n is 0. Any            one or more of the NH or NH₂ groups may be protonated so as            to provide a protonated form of the polyamine, with the            exception of NH groups adjacent to a carbonyl group, i.e.,            NH groups that form part of an amide group, since such NH            groups are not readily protonated.

In another embodiment, the PPA is a protonated form of a polyaminehaving the formula (II)

wherein

a, b, and c independently range from 1 to 10 and d and e independentlyrange from 0 to 30;

R₁ and R₃ may be the same or different and are independently selectedfrom H or from the group of a straight or branched C₁₋₅₀ saturated orunsaturated aliphatic, carboxyalkyl, carbalkoxyalkyl, or alkoxy; a C₁₋₈alicyclic; a single or multiring aryl substituted or unsubstitutedaliphatic; an aliphatic-substituted or unsubstituted single or multiringaromatic; a single or multiring heterocyclic; a single or multiringheterocyclic aliphatic; a C₁₋₁₀ alkyl; an aryl sulfonyl; or cyano; and

R₂ and R₄ may be the same or different and are independently selectedfrom the group of a straight or branched C₁₋₅₀ saturated or unsaturatedaliphatic, carboxyalkyl, carbalkoxyalkyl, or alkoxy; a C₁₋₈ alicyclic; asingle or multiring aryl substituted or unsubstituted aliphatic; analiphatic-substituted or unsubstituted single or multiring aromatic; asingle or multiring heterocyclic; a single or multiring heterocyclicaliphatic; a C1-10 alkyl; an aryl sulfonyl; or cyano. Any one or more ofthe NH or NH₂ groups may be protonated so as to provide a protonatedform of the polyamine, with the exception of NH groups that are notbasic, such as NH groups adjacent to a carbonyl group, i.e., NH groupsthat form part of an amide group, since such NH groups are not readilyprotonated.

In another embodiment, the PPA is a protonated form of a polyaminehaving the formula (III):

wherein

a, b, and c independently range from 1 to 10 and d and e independentlyrange from 0 to 30;

R₁ and R₃ may be the same or different and are independently selectedfrom H or from the group of a straight or branched C₁₋₅₀ saturated orunsaturated aliphatic, carboxyalkyl, carbalkoxyalkyl, or alkoxy; a C₁₋₈alicyclic; a single or multiring aryl substituted or unsubstitutedaliphatic; an aliphatic-substituted or unsubstituted single or multiringaromatic; a single or multiring heterocyclic; a single or multiringheterocyclic aliphatic; a C1-10 alkyl; an aryl sulfonyl; or cyano; and

R₂ and R₄ may be the same or different and are independently selectedfrom the group of a straight or branched C₁₋₅₀ saturated or unsaturatedaliphatic, carboxyalkyl, carbalkoxyalkyl, or alkoxy; a C₁₋₈ alicyclic; asingle or multiring aryl substituted or unsubstituted aliphatic; analiphatic-substituted or unsubstituted single or multiring aromatic; asingle or multiring heterocyclic; a single or multiring heterocyclicaliphatic; a C₁₋₁₀ alkyl; an aryl sulfonyl; or cyano. Any one or more ofthe NH or NH₂ groups may be protonated so as to provide a protonatedform of the polyamine, with the exception of NH groups that are notbasic, such as NH groups adjacent to a carbonyl group, i.e., NH groupsthat form part of an amide group, since such NH groups are not readilyprotonated.

In another embodiment, the PPA is a protonated form of a polyaminehaving the formula (IV)

wherein

a, b, and c independently range from 1 to 10 and d and e independentlyrange from 0 to 30;

Z₁ is NR₁R₃ and Z₂ is selected from —R₁, —CHR₁R₂ or —CR₁R₂R₃ or Z₂ isNR₁R₃ and Z₁ is selected from —R₁, —CHR₁R₂ or —CR₁R₂R₃, wherein R₁ andR₂ may be the same or different and are independently selected from H orfrom the group of a straight or branched C₁₋₅₀ saturated or unsaturatedaliphatic, carboxyalkyl, carbalkoxyalkyl, or alkoxy; a C₁₋₈ alicyclic; asingle or multiring aryl substituted or unsubstituted aliphatic; analiphatic-substituted or unsubstituted single or multiring aromatic; asingle or multiring heterocyclic; a single or multiring heterocyclicaliphatic; a C₁₋₁₀ alkyl; an aryl sulfonyl; or cyano; and

R₃ is selected from the group of a straight or branched C₁₋₅₀ saturatedor unsaturated aliphatic, carboxyalkyl, carbalkoxyalkyl, or alkoxy; aC₁₋₈ alicyclic; a single or multiring aryl substituted or unsubstitutedaliphatic; an aliphatic-substituted or unsubstituted single or multiringaromatic; a single or multiring heterocyclic; a single or multiringheterocyclic aliphatic; a C₁₋₁₀ alkyl; an aryl sulfonyl; or cyano. Anyone or more of the NH or NH₂ groups may be protonated so as to provide aprotonated form of the polyamine, with the exception of NH groups thatare not basic, such as NH groups adjacent to a carbonyl group, i.e., NHgroups that form part of an amide group, since such NH groups are notreadily protonated

In another embodiment, the PPA is a protonated form of a polyaminehaving the formula (1501), where any one or more of the NH or NH₂ groupsmay be protonated so as to provide a protonated form of the PPA, withthe exception of NH groups that are not basic, such as NH groupsadjacent to a carbonyl group, i.e., NH groups that form part of an amidegroup, since such NH groups are not readily protonated.

where an exemplary salt is formed from components having the structures

In another embodiment, the PPA is a protonated form of a polyaminehaving the formula (1505), where any one or more of the NH or NH₂ groupsmay be protonated so as to provide a protonated form of the polyamine,with the exception of NH groups that are not basic, such as NH groupsadjacent to a carbonyl group, i.e., NH groups that form part of an amidegroup, since such NH groups are not readily protonated.

In another embodiment, the PPA is a protonated form of a polyaminehaving the formula (2030), where any one or more of the NH or NH₂ groupsmay be protonated so as to provide a protonated form of the polyamine,with the exception of NH groups that are not basic, such as NH groupsadjacent to a carbonyl group, i.e., NH groups that form part of an amidegroup, since such NH groups are not readily protonated.

In another embodiment, the PPA is a protonated form of a polyaminehaving the formula (1569), where any one or more of the NH or NH₂ groupsmay be protonated so as to provide a protonated form of the polyamine,with the exception of NH groups that are not basic, such as NH groupsadjacent to a carbonyl group, i.e., NH groups that form part of an amidegroup, since such NH groups are not readily protonated.

In one embodiment, the PPA is a protonated form of a polyamine havingthe formula (1426), where any one or more of the NH or NH₂ groups may beprotonated so as to provide a protonated form of the polyamine, with theexception of NH groups that are not basic, such as NH groups adjacent toa carbonyl group, i.e., NH groups that form part of an amide group,since such NH groups are not readily protonated

Any one or more, e.g., any two, three, four, five, etc. of thepolyamines of formulae (I)-(IV), 1426, 1501, 1505, 1569, 2030, DENSpm,DEHSpm, Squalamine, Deoxyspergualin, F14512, Mozobil, Trientine,Gentamicin, Polymyxin B, spermidine, and1,1′[methylethanediylidene]dinitrilodiguanidine which is also known asmethylglyoxal bis(guanylhydrazone) or MGBG, are exemplary polyamineswhich in protonated form may be a protonated polyamine pharmaceuticalagent of the present disclosure. Other molecules having a plurality ofamine groups and suitable biological activity may also be used toprovide a PPA of the present disclosure.

Hydrophobic Carboxylic Acid

As mentioned herein, in one embodiment the present disclosure relates tosalts of cationic protonated polyamines in combination with anionicmolecules comprising a carboxylate group attached to a hydrophobicmoiety. These anionic species will be referred to herein for convenienceas hydrophobic carboxylic acids (HCAs).

In one embodiment, whether a particular carboxylate-containing moleculeis a HCA depends on the water solubility of the corresponding carboxylicacid compound. In other words, whether a carboxylate compound of theformula R—C(═O)O⁻ is a HCA depends on the water solubility of thecorresponding carboxylic acid compound of the formula R—C(═O)OH. Invarious embodiments, an HCA of the present disclosure is the carboxylateform of a corresponding carboxylic acid where the carboxylicacid-containing compound has a water solubility of less than 10 g/L, orless than 1 g/L, or less than 0.1 g/L, or less than 0.01 g/L in water,as determined at a temperature of 25° C. and a pH of 7. Compendiums ofthe water solubility of carboxylic acid-containing compounds may befound in, e.g., Yalkowsky S H, Dannenfelser R M; The AQUASOL database ofAqueous Solubility. Fifth ed., Tucson, Ariz.: Univ. AZ, College ofPharmacy (1992); Yalkowsky S H et al; Arizona Data Base of WaterSolubility (1989); and The Handbook of Aqueous Solubility Data, SecondEdition, edited by Yalkowsky S H, He, Y, and Jain, P, CRC Press (2010).

In one embodiment, the HCA of formula R—C(═O)O⁻ is characterized interms of the number of carbon atoms which forms the R group. Forexample, in various embodiments, the R group has at least 6 carbonatoms, or at least 7 carbon atoms, or at least 8 carbon atoms, or atleast 9 carbon atoms, or at least 10 carbon atoms, or at least 11 carbonatoms, or at least 12 carbon atoms, or at least 13 carbon atoms, or atleast 14 carbon atoms, or at least 15 carbon atoms, or at least 16carbon atoms. In addition, or alternatively, the R group may becharacterized by a maximum number of carbon atoms present in the moiety.For example, in various embodiments the R group has no more than 24carbon atoms, or no more than 23 carbon atoms, or no more than 22 carbonatoms, or no more than 21 carbon atoms, or no more than 20 carbon atoms,or no more than 19 carbon atoms, or no more than 18 carbon atoms, or nomore than 17 carbon atoms, or no more than 16 carbon atoms, or no morethan 15 carbon atoms, or no more than 14 carbon atoms, or no more than13 carbon atoms, or no more than 12 carbon atoms, or no more than 11carbon atoms, or no more than 10 carbon atoms.

When the HCA is characterized in terms of the number of carbon atomswhich forms the R group, the characterization may take the form of arange of carbon atoms. For example, the R group may be a C₈-C₁₆ R group,which refers to an R group having at least 8 carbon atoms and not morethan 16 carbon atoms. In additional embodiments, the R group is a C₈-C₁₄R group, or a C₈-C₁₂ R group, or a C₈-C₁₀ R group, or a C₁₀-C₁₂ R group,or a C₁₀-C₁₄ R group, or a C₁₀-C₁₆ R group, or a C₁₀-C₁₈ R group. Therange of carbon atoms may be selected from any two values between 8 and24, where optionally odd numbers are selected. In one embodiment, the Rgroup is formed solely from carbon and hydrogen atoms, where such an Rgroup may be referred to as a hydrocarbon group, and HCAs having ahydrocarbon R group may be referred to as fatty acid HCAs.

In addition to specifying the number of carbon atoms in the R group, theR group may be characterized in terms of its structure. In oneembodiment, the R group is aliphatic as opposed to aromatic. In oneembodiment, the R group is a straight chain hydrocarbon, i.e., containsno branches. In another embodiment, the R group is a branched chainhydrocarbon, i.e., contains at least one branch, which refers to acarbon being bonded to 3 or 4 other carbons. In another embodiment, theR group includes a cyclic component such as cyclohexyl, which may bepresent either as a substituent on the chain, or embedded within thechain to provide a structure such as C₁-C₆hydrocarbon chain—cyclohexylradical—C₁-C₆ hydrocarbon chain—C(═O)O—. In another embodiment, thehydrocarbon chain is saturated, i.e., does not contain any double ortriple or aromatic bonds. In another embodiment, the hydrocarbon chainis unsaturated. In another embodiment, the hydrocarbon group isaliphatic rather than including an aromatic portion.

Fatty acids of formula R—COOH are a convenient precursor to the HCAcomponent of formula R—COO⁻ of the salts of the present disclosure.Optionally, the HCA is derived from a fatty acid, where the fatty acidis pharmaceutical grade fatty acid. Suitable fatty acids are availablefrom many commercial suppliers. For example, Sigma-Aldrich (St. Louis,Mich., USA) or Spectrum Chemical (New Brunswick, N.J., USA) providessuitable fatty acids.

For example, in one embodiment, the HCA is the corresponding carboxylateform of a fatty acid compound, such as a C₈-C₁₆ straight chainhydrocarbon fatty acid. Exemplary fatty acids of this type includeoctanoic acid (also known as caprylic acid), nonanoic acid, decanoicacid (also known as capric acid), undecanoic acid, dodecanoic acid (alsoknown as lauric acid), tridecanoic acid, tetradecanoic acid andhexadecanoic acid. In one embodiment, the fatty acid is octanoic acid.In another embodiment, the fatty acid is nonanoic acid. In anotherembodiment, the fatty acid is decanoic acid. In another embodiment thefatty acid is undecanoic acid. In another embodiment, the fatty acid isdodecanoic acid. In another embodiment, the fatty acid is tridecanoicacid. In another embodiment, the fatty acid is tetradecanoic acid. Inanother embodiment, the fatty acid is hexadacanoic acid.

As another example, in one embodiment, the HCA is the correspondingcarboxylate form of a hydrocarbon group attached to a carboxylic acidgroup, where the hydrocarbon group may be, for example an aliphatichydrocarbon group having 8-18, or 10-16 carbon atoms. Such hydrocarbongroups may be straight chain to provide fatty acids such as octanoicacid, decanoic acid, dodecanoic acid, tetradecanoic acid etc. asdescribed above. Alternatively, such hydrocarbon groups may contain oneor more branches in the carbon chain.

The HCA may or may not be a pharmaceutically active agent, although inone embodiment the HCA is not a pharmaceutically active agent.Optionally, the HCA is not a polypeptide or protein, and optionallyneither of the PPA or the HCA is a polypeptide or protein. Optionally,the HCA is not a polynucleotide, and optionally neither of the PPA orthe HCA is a polynucleotide.

In one embodiment the HCA is pure. In other words, the HCA constitutesgreater than 90 wt. %, or greater than 95 wt. %, or greater than 96 wt.%, or greater than 97 wt. %, or greater than 98 wt. %, or greater than99 wt. % of the carboxylate-containing compounds present in the saltmolecule.

While the HCA may be the carboxylate form of a fatty acid, the HCA isnot necessarily the carboxylate form of a fatty acid. Other carboxylicacid-containing compounds of formula R—COOH which may give rise to a HCAof formula R—C(═O)O-include cholic acid. In additional embodiments,organic carboxylic acids of polyethylene glycol functionality may beused, i.e., the R group of R—COOH may include the (CH₂—CH₂—O)_(n) groupwhere n is 1-20. In one embodiment, the HCA may contain more than onecarboxylate group, e.g., it may be a dicarboxylate or tricarboxylateHCA, where examples include oxalic and citric acids. In one embodiment,the salts of the present disclosure are formed between a protonatedpolyamine and a lipid sulfonate formed from a lipid sulfonic acid.

Combination of Polyamine and Carboxylic Acid

As mentioned herein, in one embodiment the present invention providessalts of cationic protonated polyamines and anionic hydrophobiccarboxylates. The salts may optionally be denoted by the term (polyaminemH⁺) (R—COO⁻)_(m) where m is 1 when the salt is a monocarboxylate salt,m is 2 when the salt is a dicarboxylate salt, m is 3 when the salt is atricarboxylate salt, m is 4 when the salt is a tetracarboxylate salt,etc. The R group is selected to that the compound of formula R—COOH ishydrophobic (lipophilic), i.e., not very water soluble and mayoptionally be described as water insoluble, where exemplary R groupshave about 9 carbons (e.g., capric acid) up to about 23 carbons (e.g.,cholic acid). The polyamine will be in protonated form where, ingeneral, the more basic amine groups will be protonated first, wheretertiary amine groups are generally more basic than secondary aminegroups, and secondary amine groups are generally more basic than primaryamine groups.

The composition of the salts of the present disclosure will depend, inlarge part, on the specific components used to prepare the salt, and therelative amounts of the components that are used to prepare the salt. Ingeneral, when preparing the salts, the polyamine component may beprovided as the neutral free base form or as a charged salt form whichincludes a counterion, and more specifically an anion. Likewise, thecarboxylate component may be provided as the neutral free carboxylicacid form or as a charged salt form which includes a counterion, andmore specifically a cation. The charged salt form of the polyamine maybe referred to as an acid addition salt of the polyamine, while thecharged salt form of the hydrophobic carboxylate may be referred to asthe base addition salt of the carboxylic acid. These salts may beprepared by methods as disclosed herein. A therapeutically acceptablesalt of the present disclosure comprises a polyamine pharmaceuticalagent in cationic (protonated) form and a pharmaceutically acceptablehydrophobic carboxylic acid species in anionic (deprotonated) form, suchas disclosed herein.

For example, in one embodiment the present disclosure provides a saltformed between an organic cationic species and an organic anionicspecies. The cationic species is a protonated polyamine pharmaceuticalagent, which refers to a pharmaceutical agent that has at least oneamine group in a protonated form. The anionic species is a deprotonatedcarboxylic acid, which refers to a carboxylic acid that has transferredits acid proton to the polyamine pharmaceutical agent, thereby providinga protonated pharmaceutical agent and a deprotonated carboxylic acid.The salt may optionally be in a solid dosage form, suitable foradministration to a patient in a therapeutic method. Optionally, theanionic hydrophobic carboxylate is a carboxylate form of a fatty acidselected from C₈-C₁₈ fatty acids; the cationic protonated polyaminepharmaceutical agent is a protonated form of a therapeutically effectivepolyamine, where the polyamine does not include peptides or proteins;and/or the cationic protonated polyamine pharmaceutical agent has from 2to 4 amine groups that are independently protonatable in water, and atleast one of those protonatable amine groups is protonated to providethe cationic protonated polyamine pharmaceutical agent. The salt may befurther described by one or more of the following: the salt has twomoles of anionic hydrophobic carboxylate for each one mole of thecationic protonated polyamine pharmaceutical agent; the cationicprotonated polyamine pharmaceutical agent is a protonated form of apolyamine of Formula (1) and the anionic hydrophobic carboxylate is acarboxylate form of a fatty acid selected from C₈-C₁₄ fatty acids,

wherein, a, b, and c independently range from 1 to 10; d and eindependently range from 0 to 30; each X is independently either acarbon (C) or sulfur (S) atom; R₁ and R₂ are independently selected fromH or from the group of (i) a straight or branched C₁₋₅₀ saturated orunsaturated aliphatic, carboxyalkyl, carbalkoxyalkyl, or alkoxy; (ii) aC₁₋₈ alicyclic; (iii) a single or multiring aryl substituted orunsubstituted aliphatic; (iv) an aliphatic-substituted or unsubstitutedsingle or multiring aromatic; (v) a single or multiring heterocyclic;(vi) a single or multiring heterocyclic aliphatic; (vii) a C1-10 alkyl;(viii) an aryl sulfonyl; (ix) or cyano; or (x) R2X(O)n- is replaced byH; wherein * denotes a chiral carbon position; and wherein if X is Cthen n is 1; if X is S then n is 2; and if X is C then the XO group maybe CH2 such that n is 0; optionally, the cationic protonated polyaminepharmaceutical agent is a di-protonated form of a polyamine of formulaAMXT 1501 and the anionic hydrophobic carboxylate is deprotonated capricacid, and the salt has two moles of deprotonated capric acid for eachone mole of protonated AMXT 1501 having the formula

the salt is not in admixture with more than 5 wt % of any other solid orliquid chemical; the salt is in the form of a pharmaceuticalcomposition; the salt is in the form of a pharmaceutical composition forsolid dosage administration.

In a convenient process for preparing salts of the present disclosure,the combination of polyamine and fatty acid or other hydrophobiccarboxylic acid does not include any additional anions or cations. Sucha combination may be prepared by combining the free base form of thepolyamine with the free acid form of the fatty acid or HCA. Thecombination will be in the form of a salt, where the salt forms betweenthe protonated polyamine and the deprotonated fatty acid (ordeprotonated HCA). Thus, a convenient process for preparing the salts ofthe present disclosure is to combine an uncharged polyaminepharmaceutical with an uncharged hydrophobic carboxylic acid in asolvent under proton transfer conditions to form a salt of a positivelycharged polyamine pharmaceutical, i.e., a cationic polyaminepharmaceutical and a negatively charged hydrophobic carboxylate, i.e.,an anionic hydrophobic carboxylate, and separating the salt from thesolvent.

For example, a convenient process for preparing salts of the presentdisclosure entails combining the free base form of the polyamine withthe free acid form of the hydrophobic carboxylic acid in a solvent thatallows for proton transfer involving the carboxylic acid and thepolyamine. Thus, the present disclosure provides a method comprising:combining a polyamine, a hydrophobic carboxylic acid and a solvent so asto provide a solution; and thereafter isolating a solid residue from thesolution, wherein the residue comprises a salt formed between thepolyamine and the hydrophobic carboxylic acid. Optionally, the methodmay be further characterized by any one or more (e.g., any two, anythree, any four) of the following.

The polyamine is a pharmaceutically active polyamine such as identifiedherein. For example, any of the polyamines of formulae (I)-(IV), 1426,1501, 1505, 1569, 2030, DENSpm, DEHSpm, squalamine, deoxyspergualin,F14512, Mozobil, Trientine, Gentamicin, Polymyxin B, MGBG and spermidinemay be used in the method. The hydrophobic carboxylic acid is any of thehydrophobic carboxylic acids identified herein. For example, thehydrophobic carboxylic acid may have a water solubility of less than 10g/L water, may have the formula R—COOH where R has 6-20 carbon atoms, or8-16 carbon atoms, or 10-14 carbon atoms, or may be a fatty acidselected from octanoic acid, decanoic acid, dodecanoic acid,tetradecanoic acid and hexadecanoic acid. The hydrophobic carboxylicacid may be a mixture of hydrophobic carboxylic acids. In order toprepare a high purity PPA-HCA salt, each of the polyamine and thehydrophobic carboxylic acid may be of high purity, e.g., one or both ofthe components may be, e.g., at least 90%, or at least 95%, or at least96%, or at least 97%, or at least 98%, or at least 99%, or at least99.5% pure on a weight basis. One or both of the polya mine and thehydrophobic carboxylic acid may be pharmaceutical grade, prepared byGMP. In one embodiment, the polyamine is AMXT 1501 and the hydrophobiccarboxylic acid is capric acid.

The polyamine and the hydrophobic carboxylic acid may be combined inrelative amounts so as to provide the desired salt stoichiometry. Forexample, if a 1:1 molar stoichiometry PPA:HCA salt is desired, thenequal, or approximately equal, molar amounts of polyamine andhydrophobic carboxylic acid are combined with the solvent. Thus, in oneembodiment, about 1.0 mole, e.g., 0.9-1.1 moles of hydrophobiccarboxylic acid are combined with each 1.0 mole of polyamine. If a 1:2molar stoichiometry PPA:HCA salt is desired, then exactly or about 2.0moles, e.g., 1.8-2.2 moles of hydrophobic carboxylic acid are combinedwith each 1.0 mole of polyamine. If a 1:3 molar stoichiometry of PPA:HCSsalt is desired, then exactly or about 3.0 moles, e.g., 2.7-3.3 moles ofhydrophobic carboxylic acid are combined with each 1.0 mole ofpolyamine. If a 1:4 molar stoichiometry PPA:HCA salt is desired, thenexactly or about 4.0 moles, e.g., 3.6-4.4 moles of hydrophobiccarboxylic acid are combined with each 1.0 mole of polyamine. In oneembodiment, 1 mole of the polyamine AMXT 1501 is combined with 2 molesof the hydrophobic carboxylic acid capric acid. To be clear, whenreference is made to, e.g., 1.8-2.2 moles of hydrophobic carboxylic acidbeing combined with each 1.0 mole of polyamine, that excludes combiningless than about 1.8 moles or more than about 2.2 moles of hydrophobiccarboxylic acid with each 1.0 mole of polyamine.

The solvent should facilitate proton transfer between the hydrophobiccarboxylic acid and the polyamine. For example, the solvent may be apure polar protic solvent or it may be a mixture of solvents comprisinga polar protic solvent. A suitable polar protic solvent is water, e.g.,a water selected from deionized water and distilled water. Anothersuitable polar protic solvent is a lower-chain alcohol, e.g., methanolor ethanol. In one embodiment, 1 mole of the polyamine AMXT 1501 iscombined with 2 moles of the hydrophobic carboxylic acid capric acid ina solvent selected from water and methanol.

The components may be combined in any order so as to form a solution.For example, the polyamine and the hydrophobic carboxylic acid may beadded to the solvent so as to provide the solution. In one embodiment,the polyamine is dissolved in the solvent, and then the hydrophobiccarboxylic acid is gradually added to the solution of solvent andpolyamine. The process may be performed in a batch or a continuous mode.In a batch mode, a container receives the full charge of solvent,polyamine and hydrophobic carboxylic acid, the salt is formed in thecontainer. The polyamine, the hydrophobic carboxylic acid and thesolvent may be combined so as to provide a clear solution, in otherwords, there is no insoluble material present in the solution.Typically, the polyamine, the hydrophobic carboxylic acid and thesolvent are combined at a temperature within the range of 10-30° C.,although other temperatures may be used. In a continuous mode,continuous flow techniques could be used for the production andisolation of the PPA:HCA salt forms described. Use of available flowapparatus, wherein solutions of the polyamine free base, in a suitablesolvent such as methanol, are mixed with a co-solvent in which the saltis not soluble, such as acetonitrile, in a flow cell apparatus, allowingthe continuous production of the insoluble, or soluble form of thePPA:HCA salt.

After the salt is formed, the solvent is separated from the salt toprovide a residue that is, or includes, the salt. When the solvent isnot too volatile, then it may be removed from the solution by a processsuch as evaporation or distillation, so as to isolate the residue fromthe solution. As another option, a co-solvent (an example beingacetonitrile) may be added to the solution, whereupon a precipitatecomes out of solution, and the resulting solution is referred to as thesupernatant. The co-solvent may also be referred to as a non-solvent,since the salt is not soluble in the non-solvent. The precipitate, alsoreferred to as a residue, may be separated from the residue, e.g., bydecantation, so as to isolate the residue from the solution. As yetanother option, the solution may be chilled to a temperature such thatthe salt is no longer soluble in the solvent and thus forms the residuein the form of a precipitate. As in the case when a co-solvent is usedto form the precipitate, the supernatant may be separated from theresidue so as to isolate the residue from the solution.

In one embodiment, the residue comprises at least 50%, or at least 95%,or at least 99% by weight of the salt. In other words, at least 50% ofthe weight of the residue is the PPA:HCA salt, or at least 95% of theweight of the residue is the PPA:HCA salt, or at least 99% of the weightof the residue is the PPA:HCA salt. For example, in order to obtain thisyield, most or all of the solvent is removed from the residue so that itis essentially solvent-free. Also, in one embodiment, the residue onlycontains PPA:HCA and contains no other materials, or contains only aminor amount (e.g., less than 1, or less than 2, or less than 3 wt %) ofother materials such as residual polyamine or residual hydrophobiccarboxylic acid. Other materials may, however, be combined with thesolvent, e.g., a preservative or antimicrobial agent, so that theresidue is not entirely composed of PPA:HCA. In one embodiment, theresidue contains little or no (e.g., less than 1, or less than 2, orless than 3 wt %) inorganic species such as chloride or phosphate. Inone embodiment the residue consists of, or consists essentially of,polyamine, hydrophobic carboxylic acid, and salt formed therebetween.

Once the residue is formed, it or a portion thereof may be combined withadditional components as described herein so as to form a pharmaceuticalcomposition suitable for administration to a subject, e.g., byingestion. Those additional components may include diluents, e.g.lactose and microcrystalline cellulose, disintegrants, e.g. sodiumstarch glycolate and croscarmellose sodium, binders, e.g. PVP and HPMC,lubricants, e.g. magnesium stearate, and glidants, e.g. colloidal SiO₂.For example, the method may further comprise forming a solid dosage formselected from a pill, a tablet, a capsule, a lozenge, a caplet, and apastille, from the residue or a portion thereof. The PPA-HCA salt may bein sterile form, so as to be used in the manufacture of a pharmaceuticalagent.

As mentioned above, a charged form of the polyamine and/or a chargedform of the hydrophobic carboxylic acid may be utilized as a reactant toprepare a PPA:HCA of the present disclosure.

An acid addition salt of a polyamine may be formed by bringing thepolyamine into contact with a suitable inorganic or organic acid underconditions known to the skilled person. An acid addition salt may, forexample, be formed using an inorganic acid. Suitable inorganic acids maybe selected from the group consisting of hydrochloric acid, hydrobromicacid, sulphuric acid and phosphoric acid. An acid addition salt may alsobe formed using an organic acid. Suitable organic acids may be selectedfrom the group consisting of trifluoroacetic acid, citric acid, maleicacid, oxalic acid, acetic acid, formic acid, benzoic acid, fumaric acid,succinic acid, tartaric acid, lactic acid, pyruvic acid, methanesulfonicacid, benzenesulfonic acid and para-toluenesulfonic acid.

A base addition salt of a carboxylic acid may be formed by bringing thecarboxylic acid into contact with a suitable inorganic or organic baseunder conditions known to the skilled person. Suitable inorganic baseswhich form suitable base addition salts include the hydroxide form ofany of lithium, sodium, potassium, calcium, magnesium or barium.Suitable organic bases which form suitable base addition salts includealiphatic, alicyclic or aromatic organic amines such as methylamine,trimethylamine and picoline, alkylammonias and ammonia.

In a convenient process for preparing salts of the present disclosure,the polyamine is provided as its free base form, while the carboxylicacid is provided as its protonated acid form, and these components aremixed together. In this case, and depending on the stoichiometry of thecomponents, the combination of polyamine and carboxylic acid may resultin four species: polyamine, carboxylic acid, cation and anion. Thecation may be selected from, for example, proton, ammonium, sodium, andcalcium. The anion may be selected from, for example, hydroxide,carboxylate, and halide such as fluoride, chloride and iodide. Uponmixing, the cation and anion will form a salt, and the polyamine and thecarboxylic acid will form a salt of the present disclosure, assuming themixing is performed under conditions which allow for PPA:HCA saltformation, which typically requires the presence of water.

The combination of polyamine (in charged or uncharged form) andcarboxylic acid (in charged or uncharged form) may be characterized interms of the molar ratio of the two components. In the followingdiscussion, the term polyamine refers to both charged and unchargedpolyamine, and the term carboxylic acid refers to both charged anduncharged carboxylic acid. The relative amounts of polyamine andcarboxylic acid present in the composition may be varied. In part, therelative amounts may reflect the number of amine groups present in thepolyamine. As mentioned previously, in one embodiment the polyamine hastwo amine groups, while in another embodiment the polyamine has threeamine groups, and in yet another embodiment the polyamine has four aminegroup, while in still another embodiment the polyamine has five aminegroups, and in a further embodiment the polyamine has six or more aminegroups, where amine groups are selected from primary, secondary andtertiary amines, independently selected at each occurrence. The aminegroups are so-called protonatable amine groups, which refers to an aminegroup which is capable of bonding with a proton so as to form a chargedammonium species. NH groups adjacent to a carbonyl group, i.e., amidegroups, are not protonatable amine groups since the protonated form ofan amide group is unstable. The skilled organic chemist recognizesand/or may readily determine using known techniques, which amine groupsmay be protonated in dilute solution with a proton acid. In general,primary, secondary and tertiary amine groups are typically protonatable.

In one embodiment, each mole of polyamine is associated with 1, or withabout 1 mole of HCA to form an exemplary salt of the present disclosure.An exemplary salt is conveniently formed by combining 1 mole of PPA with1 mole of HCA, so that the salt has a 1:1, or about a 1:1 molar ratio ofPPA to HCA. However, the present disclosure also provides that more orless than 1 mole of HCA may be combined with each 1 mole of PPA. In sucha situation, the resulting 1:1 PPA:HCA salt, optionally designated asPPA:(HCA)₁, may be in admixture with unprotonated PPA or diprotonatedPPA, depending on how much HCA is combined with the PPA. For example, acomposition of the present disclosure may include a salt having a 1:1molar ratio of PPA to HCA, where this salt is in combination withnon-protonated polyamine. In addition, the present disclosure provides asalt having a 1:2 molar ratio of PPA to HCA, optionally denoted asPPA:(HCA)₂, where this salt may be in combination with a salt having a1:1 molar ratio of PPA to HCA. In one embodiment, each mole of polyamineis associated with 2, or with about 2 moles of HCA to form a salt of thepresent disclosure. Such a salt has a 1:2, or about a 1:2 molar ratio ofPPA to HCA. In addition, the present disclosure provides a salt having a1:3 molar ratio of PPA to HCA, optionally denoted as PPA:(HCA)₃, wherethis salt is in combination with a salt having a 1:2 molar ratio of PPAto HCA, optionally denoted as PPA:(HCA)₂, to provide aPPA:(HCA)₃/PPA:(HCA)₂ mixture.

The relative amounts of polyamine and carboxylic acid may be describedin terms of equivalents, where 1 mole of polyamine with 5 amine groupshas 5 equivalents of amine and 1 mole of carboxylic acid with 1carboxylic acid group has 1 equivalent of carboxylic acid. For example,when the polyamine is AMXT 1501, there are four amine groups present inthe molecule. In one embodiment of the invention, two moles of AMXT 1501are combined with 1 mole of carboxylic acid, such that the polyamine andcarboxylic acid are combined in an 8:1 equivalent ratio (8 equivalentsof amine groups and 1 equivalent of carboxyl groups). In anotherembodiment of the invention, 1 mole of AMXT 1501 is combined with 4moles of carboxylic acid, such that the polyamine and carboxylic acidare combined in a 1:1 equivalent ratio. As a further example, 1 mole ofAMXT 1501 is combined with 8 moles of carboxylic acid, such that thepolyamine and carboxylic acid are combined in a 1:2 equivalent ratio(there being 4 amine groups for every 8 carboxyl groups, providing for a1:2 equivalent ratio). Thus, as an illustration, a AMXT 1501:(capricacid)₂ salt, i.e., the dicaprate salt of AMXT 1501, may be in admixturewith, e.g., some AMXT 1501:(capric acid)₁ salt, i.e., the monocapratesalt of AMXT 1501, and/or some AMXT 1501(capric acid)₃ salt, i.e., thetricaprate salt of AMXT 1501. Likewise, a AMXT 1501:(capric acid)₁ saltmay be in admixture with, e.g., some AMXT 1501 and/or some AMXT1501(capric acid)₂ salt. In this illustration, AMXT 1501 is used as anexemplary polyamine, however, other polyamines as disclosed herein maybe substituted for AMXT 1501 in this illustration.

In one embodiment, the present disclosure provides a method forpreparing a salt of the present disclosure, where the method comprisescombining a polyamine pharmaceutical agent, a hydrophobic carboxylicacid and a solvent so as to provide a solution; and isolating a solidresidue from the solution, wherein the solid residue comprises a salt ofpresent disclosure. Optionally, the method may be described by one ormore of the following features: the solvent comprises water, methanol ora combination thereof; 1.8-2.2 moles of hydrophobic carboxylic acid arecombined with each 1.0 mole of polyamine pharmaceutical agent; the solidresidue is formed by precipitation from the solution; the method furthercomprises formulating the solid residue or portion thereof into a soliddosage form pharmaceutical.

The following are additional exemplary embodiments of PPA:HCA salts ofthe present disclosure. In one embodiment the present disclosureprovides a composition of AMXT 1501 dicaprate which is a salt form ofthe components having the molecular formulae and structures shown below:

where the components form a dicaprate salt of the polyamine and capricacid. AMXT 1501 dicaprate might also be denoted by the term (AMXT 15012H⁺) (R—COO⁻)₂ where R is C₉, e.g., n-nonyl. In general, R—COOH is notvery water soluble and may be described as water insoluble, whereexemplary R groups have about 9 carbons (e.g., capric acid) up to about23 carbons (e.g., cholic acid). The dicaprate salt may include any twoof the primary and secondary amine groups present as shown in thepolyamine in a protonated form. For example, both primary amine groupsmay be protonated, or both secondary amine groups may be protonated, orone primary and one secondary amine group may be protonated. In general,the more basic amine groups will be protonated first, where tertiaryamine groups are generally more basic than secondary amine groups, andsecondary amine groups are generally more basic than primary aminegroups. One such structure is shown below:

In one embodiment the present disclosure provides a composition of AMXT1569 dicaprate which is a salt form of the components having themolecular formulae and structures shown below:

where the components form a dicaprate salt of the polyamine and capricacid. The dicaprate salt may include any two of the primary andsecondary amine groups present as shown in the polyamine, in aprotonated form. For example, both primary amine groups may beprotonated, or both secondary amine groups may be protonated, or oneprimary and one secondary amine group may be protonated. One suchstructure is shown below:

In one embodiment the present disclosure provides a composition of AMXT2030 dicaprate which is a salt form of the components having themolecular formulae and structures shown below:

where the components form a dicaprate salt of the polyamine and capricacid. The dicaprate salt may include any two of the primary andsecondary amine groups present as shown in the polyamine, in aprotonated form. For example, both primary amine groups may beprotonated, or both secondary amine groups may be protonated, or oneprimary and one secondary amine group may be protonated. One suchstructure is shown below:

In one embodiment the present disclosure provides a composition of AMXT1426 dicaprate which is a salt form of the components having themolecular formulae and structures shown below:

where the components form a dicaprate salt of the polyamine and capricacid. The dicaprate salt may include any two of the primary andsecondary amine groups present as shown in the polyamine, in aprotonated form. For example, both primary amine groups may beprotonated, or both secondary amine groups may be protonated, or oneprimary and one secondary amine group may be protonated. One suchstructure is shown below:

In one embodiment the present disclosure provides a composition of AMXT1505 dicaprate which is a salt form of AMXT 1505 polyamine and twocapric acids, where such as a salt is shown below:

In one embodiment, the PPA is a protonated form of the polyamine knownas DENSpm, where any one or more of the NH groups of DENSpm may beprotonated and associated with a HCA so as to provide a protonated formof the polyamine. In one embodiment, one of the four NH groups presentin DENSpm is protonated and associated with an HCA so as to form a saltof the present disclosure. In one embodiment, two of the NH groups ofDENSpm are protonated and associated with HCAs so as to form a salt ofthe present disclosure. In one embodiment, three of the NH groupspresent in DENSpm are protonated and associated with HCAs to form a saltof the present disclosure. In yet another embodiment, all four of the NHgroups present in DENSpm are protonated and associated with HCAs so asto form a salt of the present disclosure. While such a salt of thepresent disclosure will necessarily comprise DENSpm in protonated formassociated with at least one HCA, the salt may also be associated withother species as mentioned herein, e.g., solvent molecules and/ornon-HCA anionic species.

In one embodiment, the PPA is a protonated form of the polyamine knownas squalamine, where any one or more of the NH and NH₂ groups ofsqualamine may be protonated and associated with a HCA so as to providea protonated form of the polyamine. In one embodiment, one of the two NHgroups present in squalamine is protonated and associated with an HCA soas to form a salt of the present disclosure. In one embodiment, two ofthe NH groups of squalamine are protonated and associated with HCAs soas to form a salt of the present disclosure. In one embodiment, the NH₂group present in squalamine is protonated and associated with an HCA soas to form a salt of the present disclosure. In yet another embodiment,one of the NH groups and the NH₂ group present in squalamine areprotonated and associated with HCAs so as to form a salt of the presentdisclosure. In still another embodiment, both of the NH groups and theNH₂ group present in squalamine are protonated and associated with HCAsso as to form a salt of the present disclosure. While such a salt of thepresent disclosure will necessarily comprise squalamine in protonatedform associated with at least one HCA, the salt may also be associatedwith other species as mentioned herein, e.g., solvent molecules and/ornon-HCA anionic species.

In one embodiment, the PPA is a protonated form of the polyamine knownas deoxyspergualin, where any one or more of the NH and NH₂ groups ofdeoxyspergualin may be protonated and associated with a HCA so as toprovide a protonated form of the polyamine. In one embodiment, one NHgroup present in deoxyspergualin is protonated and associated with anHCA so as to form a salt of the present disclosure. In one embodiment,one NH₂ group of deoxyspergualin is protonated and associated with HCAsso as to form a salt of the present disclosure. In yet anotherembodiment, one NH group and one NH₂ group present in deoxyspergualinare protonated and associated with HCAs so as to form a salt of thepresent disclosure. While such a salt of the present disclosure willnecessarily comprise deoxyspergualin in protonated form associated withat least one HCA, the salt may also be associated with other species asmentioned herein, e.g., solvent molecules and/or non-HCA anionicspecies.

In one embodiment, the PPA is a protonated form of the polyamine knownas F14512, where any one or more of the NH and NH₂ groups of F14512 maybe protonated and associated with a HCA so as to provide a protonatedform of the polyamine. In one embodiment, one of the two NH groupspresent in F14512 is protonated and associated with an HCA so as to forma salt of the present disclosure. In one embodiment, two of the NHgroups of F14512 are protonated and associated with HCAs so as to form asalt of the present disclosure. In one embodiment, three NH groups ofF14512 are protonated as associated with an HCA so as to form a salt ofthe present disclosure. In one embodiment, the NH₂ group present inF14512 is protonated and associated with an HCA so as to form a salt ofthe present disclosure. In yet another embodiment, one of the NH groupsand the NH₂ group present in F14512 are protonated and associated withHCAs so as to form a salt of the present disclosure. In still anotherembodiment, two of the NH groups and the NH₂ group present in F14512 areprotonated and associated with HCAs so as to form a salt of the presentdisclosure. While such a salt of the present disclosure will necessarilycomprise F14512 in protonated form associated with at least one HCA, thesalt may also be associated with other species as mentioned herein,e.g., solvent molecules and/or non-HCA anionic species.

In one embodiment, the PPA is a protonated form of the polyamine knownas Mozobil, where any one or more of the NH groups of Mozobil may beprotonated and associated with a HCA so as to provide a protonated formof the polyamine. In one embodiment, one of the NH groups present inMozobil is protonated and associated with an HCA so as to form a salt ofthe present disclosure. In one embodiment, two of the NH groups ofMozobil are protonated and associated with HCAs so as to form a salt ofthe present disclosure. In one embodiment, three NH groups of Mozobilare protonated as associated with an HCA so as to form a salt of thepresent disclosure. In one embodiment, four NH groups present in Mozobilare protonated and associated with an HCA so as to form a salt of thepresent disclosure. While such a salt of the present disclosure willnecessarily comprise Mozobil in protonated form associated with at leastone HCA, the salt may also be associated with other species as mentionedherein, e.g., solvent molecules and/or non-HCA anionic species.

In one embodiment, the PPA is a protonated form of the polyamine knownas Trientine, where any one or more of the NH and NH₂ groups ofTrientine may be protonated and associated with a HCA so as to provide aprotonated form of the polyamine. In one embodiment, one of the two NHgroups present in Trientine is protonated and associated with an HCA soas to form a salt of the present disclosure. In one embodiment, two ofthe NH groups of Trientine are protonated and associated with HCAs so asto form a salt of the present disclosure. In one embodiment, one NH₂group present in Trientine is protonated and associated with an HCA soas to form a salt of the present disclosure. In one embodiment, both NH₂groups present in Trientine are protonated and associated with an HCA soas to form a salt of the present disclosure. In yet another embodiment,one of the NH groups and one of the NH₂ group present in Trientine areprotonated and associated with HCAs so as to form a salt of the presentdisclosure. In still another embodiment, two of the NH groups and oneNH₂ group present in Trientine are protonated and associated with HCAsso as to form a salt of the present disclosure. In still anotherembodiment, one of the NH groups and two NH₂ groups present in Trientineare protonated and associated with HCAs so as to form a salt of thepresent disclosure. While such a salt of the present disclosure willnecessarily comprise Trientine in protonated form associated with atleast one HCA, the salt may also be associated with other species asmentioned herein, e.g., solvent molecules and/or non-HCA anionicspecies. Trientine is also known as triethylenetetramine, abbreviatedTETA, or as trien.

In one embodiment, the PPA is a protonated form of the polyamine knownas Gentamicin, where any one or more of the NH and NH₂ groups ofGentamicin may be protonated and associated with a HCA so as to providea protonated form of the polyamine. In one embodiment, one of the NHgroups present in Gentamicin is protonated and associated with an HCA soas to form a salt of the present disclosure. In one embodiment, two ofthe NH groups of Gentamicin are protonated and associated with HCAs soas to form a salt of the present disclosure. In one embodiment, one NH₂group present in Gentamicin is protonated and associated with an HCA soas to form a salt of the present disclosure. In one embodiment, two NH₂groups present in Gentamicin are protonated and associated with an HCAso as to form a salt of the present disclosure. In yet anotherembodiment, one of the NH groups and one of the NH₂ group present inGentamicin are protonated and associated with HCAs so as to form a saltof the present disclosure. In still another embodiment, two of the NHgroups and one NH₂ group present in Gentamicin are protonated andassociated with HCAs so as to form a salt of the present disclosure. Instill another embodiment, one of the NH groups and two NH₂ groupspresent in Gentamicin are protonated and associated with HCAs so as toform a salt of the present disclosure. While such a salt of the presentdisclosure will necessarily comprise Gentamicin in protonated formassociated with at least one HCA, the salt may also be associated withother species as mentioned herein, e.g., solvent molecules and/ornon-HCA anionic species.

In one embodiment, the PPA is a protonated form of the polyamine knownas Polymyxin B, where any one or more of the NH₂ groups of Polymyxin Bmay be protonated and associated with a HCA so as to provide aprotonated form of the polyamine. In one embodiment, one of the NH₂groups present in Polymyxin B is protonated and associated with an HCAso as to form a salt of the present disclosure. In one embodiment, twoof the NH₂ groups of Polymyxin B are protonated and associated with HCAsso as to form a salt of the present disclosure. In one embodiment, threeof the NH₂ groups present in Polymyxin B is protonated and associatedwith an HCA so as to form a salt of the present disclosure. In oneembodiment, four NH₂ groups present in Polymyxin B are protonated andassociated with an HCA so as to form a salt of the present disclosure.While such a salt of the present disclosure will necessarily comprisePolymyxin B in protonated form associated with at least one HCA, thesalt may also be associated with other species as mentioned herein,e.g., solvent molecules and/or non-HCA anionic species.

In one embodiment, the PPA is a protonated form of the polyamine orpolyguanidine known as MGBG, where any one or more of the NH₂ groups ofMGBG may be protonated and associated with a HCA so as to provide aprotonated form of the polyamine. In one embodiment, one of the NH₂groups present in MGBG is protonated and associated with an HCA so as toform a salt of the present disclosure. In one embodiment, two of the NH₂groups of MGBG are protonated and associated with HCAs so as to form asalt of the present disclosure. In one embodiment, three of the NH₂groups present in MGBG is protonated and associated with an HCA so as toform a salt of the present disclosure. In one embodiment, four NH₂groups present in MGBG are protonated and associated with an HCA so asto form a salt of the present disclosure. While such a salt of thepresent disclosure will necessarily comprise MGBG in protonated formassociated with at least one HCA, the salt may also be associated withother species as mentioned herein, e.g., solvent molecules and/ornon-HCA anionic species.

In one embodiment, the present disclosure provides a composition ofspermidine dicaprate. In one embodiment, the PPA is a protonated form ofthe polyamine known as spermidine, where any one or more of the NH₂groups of spermidine may be protonated and associated with a HCA so asto provide a protonated form of the polyamine. In one embodiment, one ofthe NH₂ groups present in spermidine is protonated and associated withan HCA so as to form a salt of the present disclosure. In oneembodiment, two of the NH₂ groups of spermidine are protonated andassociated with HCAs so as to form a salt of the present disclosure. Inone embodiment, two NH₂ groups and one NH group present in spermidineare protonated and associated with an HCA so as to form a salt of thepresent disclosure. While such a salt of the present disclosure willnecessarily comprise spermidine in protonated form associated with atleast one HCA, the salt may also be associated with other species asmentioned herein, e.g., solvent molecules and/or non-HCA anionicspecies. In one embodiment, the PPA is a protonated form of spermidine,which has the formula shown below, where any one or more of the NH orNH₂ groups may be protonated so as to provide a protonated form ofspermidine. For example, in one embodiment the present disclosureprovides spermidine dicaprate, which is a salt form of the componentshaving the molecular formulae and structures shown below:

for example, a salt form of the formula

The foregoing are exemplary PPA:HCA salts of the present disclosure,which may be prepared by methods as described herein. In general, thePPA:HCA salts may be conveniently prepared by neutralization of an acid(the HCA component) by the base (the PPA component) in a suitablesolvent such as water. In one embodiment, the present invention providesa composition comprising PPA, HCA and a suitable solvent to allow saltformation between PPA and HCA, e.g., water, methanol and mixturesthereof, as well as a composition consisting of, and a compositionconsisting essentially of, PPA, HCA and the suitable solvent. Such acomposition will provide a salt of the present invention in solution,from which a salt of the present disclosure may be isolated.

Pharmaceutical Formulations

The salts of the present disclosure may be administered by oral,parenteral (e.g., intramuscular, intraperitoneal, intravenous, ICV,intracisternal injection or infusion, subcutaneous injection, orimplant), by inhalation spray, nasal, vaginal, rectal, sublingual, ortopical routes of administration. The salts may be formulated, alone ortogether, into suitable dosage unit formulations, also known as dosageforms, containing conventional non-toxic pharmaceutically acceptableinert (i.e., not biologically active) components such as carriers,adjuvants and vehicles appropriate for each route of administration. Inaddition to the treatment of warm-blooded animals such as mice, rats,horses, cattle, sheep, dogs, cats, monkeys, etc., the salts of thedisclosure are effective for use in humans.

The pharmaceutical compositions for the administration of the salts ofthis disclosure may conveniently be presented in dosage unit form andmay be prepared by any of the methods well known in the art of pharmacy.The scientific field of pharmaceutics is focused on delivery ofpharmaceutical agents in a form that maximizes the benefit to thepatient being treated. Without being bound by theory, formulation ofpolyamine drugs as their carboxylic acid salts may increase thelipophilicity of the resulting salt composition, facilitating uptake bycellular components of the gastrointestinal tract of treated animals. Infact, the mammalian gastrointestinal utilizes bile acid secretion tofacilitate the dietary uptake of more lipophilic components of the diet.

All methods include the step of bringing the active ingredient, i.e.,the salt of the present disclosure, into association or combination withthe inert components which constitute one or more accessory ingredients.In general, the pharmaceutical compositions are prepared by uniformlyand intimately bringing the salt of the present disclosure intoassociation with a liquid carrier or a finely divided solid carrier orboth, and then, if necessary, shaping the product into the desiredformulation. In the pharmaceutical composition, the active salt of thepresent disclosure is included in an amount sufficient to produce thedesired effect upon the process or condition of diseases. As usedherein, the term “composition” is intended to encompass a productcomprising the specified ingredients optionally in specified amounts, aswell as any product which results, directly or indirectly, from acombination of the specified ingredients in the specified amounts.

In one embodiment, the pharmaceutical composition is a solid dosage formintended for oral use. For many reasons, an oral composition, andparticularly a solid oral dosage form, is advantageous and convenientfor both the patient and the medical practitioner responsible fordeveloping the therapeutic regime. An oral composition avoids thecomplications, cost and inconvenience of administration via IV injectionor infusion which must be done by a medical professional in a hospitalor out-patient setting which exposes him or her to hospital-basedinfections and illnesses. In particular, patients undergoing treatmentfor cancer may be immunocompromised individuals and particularlysusceptible to hospital-based infections and illnesses. An oralformulation, such as a pill or tablet, may be taken outside of ahospital setting, increasing the potential for subject ease of use andcompliance. This permits a subject to avoid infection risks concomitantwith IV administration and hospital visits. In addition, oral deliverymay avoid the high concentration peak and rapid clearance associatedwith an IV bolus dose.

Examples of oral solid dosage forms include pills, tablets, capsules,granules, and microspheres, any of which may include an enteric-coatingto protect the pharmaceutical composition from acid-degradation bystomach environment, or to maximize delivery to intestinal sectionswhere absorption is enhanced. The solid dosage form may be chewable orswallowable, or have any suitable ingestible form. In one embodiment,the solid dosage form contains little or no water, e.g., less than 0.1wt % water, or less than 0.2 wt % water, or less than 0.3 wt % water, orless than 0.4 wt % water, or less than 0.5 wt % water, or less than 1 wt% water, or less than 1.5 wt % water, or less than 2 wt % water.

Solid dosage forms may be prepared according to any method known to theart for the manufacture of pharmaceutical compositions. Suchcompositions may contain one or more inert components, where exemplaryinert components may be selected from the group of sweetening agents,flavoring agents, coloring agents and preserving agents in order toprovide pharmaceutically elegant and palatable preparations. Soliddosage forms of the present disclosure contain the salt of the presentdisclosure in optional admixture with inert and non-toxicpharmaceutically acceptable excipients which are suitable for themanufacture of the solid dosage form.

Excipients for solid dosage forms are well known in the art, and areselected to provide various benefits including ease of administration tothe subject, improved dosing compliance, consistency and control of drugbioavailability, assistance with enhanced bioavailability, improved APIstability including protection from degradation, and to contribute tothe ease of production of a robust and reproducible physical product.Excipients are commonly subdivided into various functionalclassifications, depending on the role that they are intended to play inthe formulation. For solid dosage forms, common excipient roles andexemplary materials that fulfill that role are diluents, e.g. lactoseand microcrystalline cellulose, disintegrants, e.g. sodium starchglycolate and croscarmellose sodium, binders, e.g. PVP and HPMC,lubricants, e.g. magnesium stearate, and glidants, e.g. colloidal SiO₂.Tablets and capsules often contain a diluent, filler or bulking agent,e.g., lactose. Excipients used to formulate polyamine drug agents shouldavoid those containing reducing sugar components in order to preventformation of Schiff-base addition products as degradants.

Excipients may be, for example, inert diluents, such as calciumcarbonate, sodium carbonate, and lactose; granulating and disintegratingagents, such as corn starch, and alginic acid; binding agents, such asstarch, gelatin or acacia; and lubricating agents, such as magnesiumstearate, stearic acid and talc. The tablets of the present disclosure,containing a PPA:HCA salt as disclosed herein, may be uncoated or theymay be coated, e.g., with an enteric coating, by known techniques, inorder to delay disintegration and absorption in the gastrointestinaltract and thereby provide a sustained action over a longer period.Compositions for oral use may also be formed as hard gelatin capsuleswherein the biologically active salt of the present disclosure is mixedwith an inert solid diluent, for example, calcium carbonate, kaolin, oras soft gelatin capsules wherein the salt is mixed with water or an oilmedium, for example peanut oil, liquid paraffin, or olive oil.

In one embodiment, aqueous suspensions for pharmaceutical applicationcontain the biologically active salt of the present disclosure inadmixture with excipients suitable for the manufacture of aqueoussuspensions. Oily suspensions may be formulated by suspending the activeingredient in a suitable oil. Oil-in-water emulsions may also beemployed. Dispersible powders and granules suitable for preparation ofan aqueous suspension by the addition of water provide the biologicallyactive salt of the present disclosure in admixture with a dispersing orwetting agent, suspending agent and one or more preservatives.

Pharmaceutical compositions of the salts of the present disclosure maybe in the form of a sterile injectable aqueous or oleagenous suspension.The salts of the present disclosure may be administered by subcutaneousinjection. The salts of the present disclosure may also be administeredin the form of suppositories for rectal administration. For topical use,creams, ointments, jellies, solutions or suspensions, etc., containingthe salts of the present disclosure may be employed. The salts of thepresent disclosure may also be formulated for administered byinhalation. The salts of the present disclosure may also be administeredby a transdermal patch by methods known in the art.

The pharmaceutical compositions and methods of the present disclosuremay further comprise additional therapeutically active compounds whichare beneficially applied in the treatment of a pathological conditionexperienced or potentially experienced by the subject receiving thepharmaceutically active salt of the present disclosure.

In the treatment, prevention, control, amelioration, or reduction ofrisk of cancer, the salts of the present disclosure will be administeredat an appropriate dosage level that will generally be about 0.01 to 500mg per kg patient body weight per day, which can be administered insingle or multiple doses. Human dose levels, especially those used forcancer chemotherapy, are alternatively expressed in units of mg/m²/day.The dose may be higher or lower at the discretion of the attendinghealth care professional, based on that person's experience andknowledge in dealing with the specific medical condition being treatedand the condition of the patient. Optionally, the dosage level will beabout 0.1 to about 250 mg/kg per day; or about 0.5 to about 100 mg/kgper day. A suitable dosage level may be about 0.01 to 250 mg/kg per day,about 0.05 to 100 mg/kg per day, or about 0.1 to 50 mg/kg per day.Within this range the dosage may be, for example, about 0.05 to 0.5, 0.5to 5, or 1 to 50, or 5 to 50 mg/kg per day.

For oral administration, the compositions are preferably provided in asolid form, such as the form of pills, capsules, tablets and the like,containing 1.0 to 1000 milligrams of the salt of the present disclosure,particularly about 1, 5.0, 10.0, 15.0, 20.0, 25.0, 50.0, 75.0, 100.0,150.0, 200.0, 250.0, 300.0, 400.0, 500.0, 600.0, 750.0, 800.0, 900, and1000.0 milligrams of the salt of the present disclosure for thesymptomatic adjustment of the dosage to the patient to be treated. Thesalts may be administered on a regimen of 1 to 4 times per day,preferably once or twice per day, at the discretion of the attendinghealth care professional.

In one embodiment, the solid dosage form contains 10 mg, or 20 mg, or 30mg, or 40 mg, or 50 mg, or 60 mg, or 70 mg, or 80 mg, or 90 mg, or 100mg, or 110 mg, or 120 mg, or 130 mg, or 140 mg, or 150 mg of theprotonated form of the polyamine (PPA), where that PPA will, however, bepresent in the solid dosage from as a salt with HCA. The amount of thePPA present in the solid dosage form may also be characterized in termsof a range of possible amounts, where the lower and upper limits of thatrange are selected from the amounts just described, i.e., from 10 to 150mg, or numbers in between, e.g., 50 to 100 mg. A tablet or pill willtypically have a total weight of at least 50 mg.

In one embodiment, the solid dosage form provides a therapeuticallyeffective systemic plasma level of a polyamine pharmaceutical agent fora period of at least 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 30, 36, or 48 hours. In further embodiments,the solid dosage form provides a therapeutically effective systemicplasma level of a polyamine pharmaceutical agent for at least an 8 hourperiod. In further embodiments, the solid dosage form provides atherapeutically effective systemic plasma level of a polyaminepharmaceutical agent for at least a 14 hour period. In furtherembodiments, the solid dosage form provides a therapeutically effectivesystemic plasma level of a polyamine pharmaceutical agent for at leastan 18-hour period. In further embodiments, the solid dosage formprovides a therapeutically effective systemic plasma level of apolyamine pharmaceutical agent for at least a 24-hour period.

In one embodiment, the solid dosage form provides a plasma level of apolyamine pharmaceutical agent of at least 25, 50, 55, 60, 65, 75, 80,85, 90, or 95 percent of the peak plasma concentration for at least 4hours. In certain embodiments, the solid dosage form provides a plasmalevel of a polyamine pharmaceutical agent of at least 75% of the peakplasma concentration for at least 4, 6, 8, 10, 12, 14, 16, 18, 20, 22,or 24 hours. In certain embodiments, the solid dosage form provides aplasma level of a polyamine pharmaceutical agent of at least 75% of thepeak plasma concentration for at least 4 hours. In certain embodiments,the solid dosage form provides a plasma level of a polyaminepharmaceutical agent of at least 75% of the peak plasma concentrationfor at least 6 hours. In certain embodiments, the solid dosage formprovides a plasma level of a polyamine pharmaceutical agent of at least75% of the peak plasma concentration for at least 10 hours. In certainembodiments, the solid dosage form provides a plasma level of apolyamine pharmaceutical agent of at least 50% of the peak plasmaconcentration for at least 6 hours. In certain embodiments, the soliddosage form provides a plasma level of a polyamine pharmaceutical agentof at least 50% of the peak plasma concentration for at least 12 hours.In certain embodiments, the solid dosage form provides a plasma level ofa polyamine pharmaceutical agent of at least 50% of the peak plasmaconcentration for at least 18 hours. In certain embodiments, the soliddosage form provides a plasma level of a polyamine pharmaceutical agentof at least 25% of the peak plasma concentration for at least 18 hours.In further embodiments, the peak plasma concentration is atherapeutically effective concentration. In yet further embodiments, thepercentage of peak plasma concentration is therapeutically effectiveover the given time period.

When treating, preventing, controlling, ameliorating, or reducing therisk of cell proliferative diseases such as cancer for which salts ofthe present disclosure are indicated, generally satisfactory results areobtained when the salts of the present disclosure are administered at adaily dosage of from about 0.1 milligram to about 100 milligram perkilogram of animal body weight, given as a single daily dose or individed doses two to six times a day, or in sustained release form. Formost large mammals, the total daily dosage is from about 1.0 milligramsto about 1000 milligrams, or from about 1 milligrams to about 50milligrams. This dosage regimen may be adjusted to provide the optimaltherapeutic response.

It will be understood, however, that the specific dose level andfrequency of dosage for any particular patient may be varied and willdepend upon a variety of factors including the activity of the specificsalt employed, the metabolic stability and length of action of thatsalt, the age, body weight, general health, sex, diet, mode and time ofadministration, rate of excretion, drug combination, the severity of theparticular condition, and the subject undergoing therapy. This inventionfacilitates oral and other administration routes used clinically andimproves patient compliance.

As mentioned above, the pharmaceutical composition may be formulated asa tablet, capsule or the like. For example, the pharmaceuticalcomposition may comprise 0.1-50% of a PPA-HCA; 0.1-99.9% of a filler;0-10% of a disintegrant; 0-5% of a lubricant; and, 0-5% of a glidant. Asanother example, the pharmaceutical composition comprises 0.1-50% ofPPA-HCA; 0.1-99.9% of a filler; 0-10% of a disintegrant; 0-5% of alubricant; and, 0-5% of a glidant. Optionally, the pharmaceuticalcomposition comprises 10-300 mg of a polyamine pharmaceutical agent suchas AMXT 1501 dicaprate, making up 2-50% of the tablet content or capsulefill content, 0-10% of a disintegrant, 0-5% of a lubricant, 0-5% of aglidant; and 30-98% of a filler. In another embodiment, thepharmaceutical composition comprises a desired amount of PPA:HCA,0.1-10% of a binder, 0-5% of a surfactant, 0-10% of an intergranulardisintegrant, and 0-10% of an extragranular disintegrant. Examples ofbinders, fillers, surfactants, disintegrants, lubricants, intergranulardisintegrant, extragranular disintegrant and glidants are known in theart, and examples are disclosed herein, and include, a binder selectedfrom copolyvidone, hydroxypropyl-cellulose,hydroxypropylmethylcellulose, and povidone, a filler selected from asugar, a starch, a cellulose, and a poloxamer; a surfactant selectedfrom polyoxyethylene (20) sorbitan monooleate, a poloxamer, and sodiumlauryl sulfate, an intergranular disintegrant selected fromcroscarmellose sodium, sodium starch glyconate, and crospovidone. Forinstance, a disintegrant selected from povidone and crospovidone; alubricant which is magnesium stearate; and a glidant which is silicondioxide.

For example, in one embodiment the present disclosure provides an oralpharmaceutical composition, preferably a solid dosage form, comprisingAMXT 1501 dicaprate salt together with at least one oralpharmaceutically acceptable excipient, which yields a therapeuticallyeffective systemic plasma AMXT 1501 level for at least a 12-hour periodwhen orally administered to a subject. Optionally, the composition maybe further characterized by one or more of the following: thecomposition yields a therapeutically effective systemic plasma AMXT 1501level for at least a 24-hour period when orally administered to asubject; the plasma level of AMXT 1501 is at least 75% of the peakplasma concentration for 4 or more hours; the composition has an oralbioavailability of at least 20%, or at least 30%, or at least 40%; thecomposition yields a therapeutically effective plasma level of AMXT 1501for at least a 24 hour period in the subject with once-daily dosing; thecomposition has a half-life of at least 12 hours or at least 18 hours;the composition does not have substantially dose-limiting side effects,e.g., gastrointestinal side effects such as nausea, vomiting, diarrhea,abdominal pain, oral mucositis, oral ulceration, pharyngitis,stomatitis, and gastrointestinal ulceration; the composition comprisesabout 25 mg to about 350 mg of AMXT 1501 in salt form; the compositionis formulated as a tablet or capsule. In this exemplary embodiment, AMXT1501 is used as an exemplary polyamine pharmaceutical agent and capricacid used as an exemplary hydrophobic carboxylic acid.

PPA-HCA Salts in Therapy

Of the myriad delivery modes for pharmaceutical agents, the oral routeis by far the most optimum by consideration of patient convenience andcompliance and is favored for biochemical targets that requiresustained, durable engagement. The natural ability of the patients, bethis a human or animal, to eliminate drug agents from the blood streamis balanced by continuous uptake via the oral route. Multiple doses canbe conveniently administered over the course of a day. Patients can takethese drugs in their homes or workplaces. Because of these specificreasons, optimization of the delivery of orally formulated drugs is anongoing goal of pharmaceutical development process.

Delivery of PPAs in their hydrochloride salt forms is a generally usedmethod for their initial animal and human testing. Examples of these aregiven in the above specification. Several PPAs have been approved forclinical use, despite challenges associated with their delivery. Thepresent disclosure provides for the identification, preparation and useof polyamine pharmaceutical agents for their intended or desiredtherapeutic purposes, but in an easily administered and effective oralcomposition to achieve their intended or desired medicinal purpose.

In one embodiment, the present disclosure provides a method of treatingcancer comprising administering to a subject in need thereof atherapeutically effective amount of a salt of the present disclosure.The PPA component of the salt of the present disclosure will be selectedin order to be effective in the treatment of the cancer that needstreatment. The cancer may be, for example, breast cancer, prostatecancer, colon cancer or lung cancer. Other cancers that may be treatedby appropriate selection of the PPA include neuroblastoma, pancreatic,bladder, melanoma, skin cancer, non-Hodgkin lymphoma, kidney cancer,head and neck cancers including glioblastoma, leukemia and other bloodcancers, ovarian and thyroid cancers. The cancer may be a solid tumor.The cancer may be treated by PPAs that are specific for oncogenes, e.g.,MYCN and RAS derived tumors. In one embodiment, the cancer is treated byadministration of AMXT 1501 dicaprate salt, i.e., a compound of theformula PPA:(HCA)₂ where PPA is AMXT 1501 and HCA is capric acid, whereadministration may be by a solid oral dosage form.

In general, there is a myriad of therapeutic uses provided bypolyamine-based therapeutics in addition to anti-cancer treatments.Polyamine-based agents have been described to have antibioticactivities, anti-viral actions, anti-inflammatory actions, anti-sepsisactivity, anti-pain abilities, anti-psychotic actions, anti-agingeffects, anti-heart damage effects, among many other actions. Oraldelivery of these polyamine active agents would greatly benefit theirdesired pharmacological actions and improve therapeutic benefit forpatients undergoing therapy for these aliments.

EXEMPLARY EMBODIMENTS

Reference throughout this specification to “one embodiment” or “anembodiment” and variations thereof means that a particular feature,structure, or characteristic described in connection with the embodimentis included in at least one embodiment. Thus, the appearances of thephrases “in one embodiment” or “in an embodiment” in various placesthroughout this specification are not necessarily all referring to thesame embodiment. Furthermore, the particular features, structures, orcharacteristics may be combined in any suitable manner in one or moreembodiments.

The following provides exemplary embodiments of the present disclosure.

-   -   1) A salt of a cationic protonated polyamine pharmaceutical        agent and an anionic hydrophobic carboxylate.    -   2) The salt of any of embodiments 1 and 3-9 wherein the anionic        hydrophobic carboxylate is a carboxylate form of a fatty acid        selected from C₈-C₁₈ fatty acids.    -   3) The salt of any of embodiments 1-2 and 4-9 wherein the        anionic hydrophobic carboxylate is a carboxylate form of a fatty        acid selected from octanoic acid, decanoic acid, dodecanoic acid        and tetradecanoic acid, or a fatty acid selected from decanoic        acid, dodecanoic acid and tetradecanoic acid.    -   4) The salt of any of embodiments 1-3 and 5-9 wherein the        anionic hydrophobic carboxylate is a carboxylate form of an        organic carboxylic acid having a water solubility of less than        10 g/L as determined in water at 25° C. and pH 7.    -   5) The salt of any of embodiments 1-4 and 6-9 wherein the        cationic protonated polyamine is a protonated form of a        therapeutically effective polyamine that has from 2 to 4 amine        groups that are independently protonatable in water, and at        least one of those protonatable amine group is protonated to        provide the cationic protonated polyamine.    -   6) The salt of any of embodiments 1-5 and 7-9 wherein the        cationic protonated polyamine is a protonated form of a        therapeutically effective polyamine that has from 2 to 4 amine        groups that are independently protonatable in water, and at        least two of those protonatable amine group are protonated to        provide the cationic protonated polyamine.    -   7) The salt of any of embodiments 1-6 and 9 comprising from 1.5        to 2.5 moles of anionic hydrophobic carboxylate for every 1 mole        of cationic protonated polyamine.    -   8) The salt of any of embodiments 1-7 wherein the cationic        protonated polyamine is a protonated form of a therapeutically        effective polyamine as disclosed herein, for example, a        polyamine having the formula (I)

wherein

-   -   a, b, and c independently range from 1 to 10;    -   d and e independently range from 0 to 30;    -   each X is independently either a carbon (C) or sulfur (S) atom;    -   R₁ and R₂ are independently selected from H or from the group of        -   a straight or branched C₁₋₅₀ saturated or unsaturated            aliphatic, carboxyalkyl, carbalkoxyalkyl, or alkoxy;        -   a C₁₋₈ alicyclic;        -   a single or multiring aryl substituted or unsubstituted            aliphatic;        -   an aliphatic-substituted or unsubstituted single or            multiring aromatic;        -   a single or multiring heterocyclic;        -   a single or multiring heterocyclic aliphatic;        -   a C₁₋₁₀ alkyl;        -   an aryl sulfonyl;        -   or cyano; or        -   R₂X(O)_(n)— is replaced by H;            wherein * denotes a chiral carbon position; and            wherein if X is C then n is 1; if X is S then n is 2; and if            X is C then the XO group may be CH₂ such that n is 0.    -   9) The salt of any of embodiments 1-7 wherein the cationic        protonated polyamine is a protonated form of spermidine, for        example, spermidine dicaprate.    -   10) A process for preparing a salt, the process comprising        combining an uncharged polyamine pharmaceutical with an        uncharged hydrophobic carboxylic acid in a solvent under proton        transfer conditions to form a salt of a charged polyamine        pharmaceutical and a charged hydrophobic carboxylate, and        separating the salt from the solvent.    -   11) The process of any of embodiments 10 and 12-15 wherein the        solvent comprises methanol.    -   12) The process of any of embodiments 10-11 and 13-15 wherein        about 2 moles of the uncharged carboxylic acid are combined with        every 1 mole of uncharged polyamine pharmaceutical.    -   13) The process of any of embodiments 10-12 and 14-15 wherein        the uncharged carboxylic acid is added to a solution comprising        the solvent and the uncharged polyamine pharmaceutical.    -   14) The process of any of embodiments 10-13 and 15 wherein the        uncharged carboxylic acid is added to a solution comprising the        solvent and the uncharged polyamine pharmaceutical, and a salt        is thereby formed as a precipitate.    -   15) The process of any of embodiments 10-14 which is conducted        at a temperature of about 25° C.    -   16) A pharmaceutical composition for oral administration to a        subject, the composition comprising a salt of a cationic        protonated polyamine pharmaceutical agent and an anionic        hydrophobic carboxylate, the composition being suitable for oral        administration.    -   17) The composition of any of embodiments 16 and 18-21 in a        solid form.    -   18) The composition of any of embodiments 16-17 and 19-21 in a        solid form selected from a capsule, a tablet, and a pill.    -   19) The composition of any of embodiments 16-18 and 20-21 in a        solid form having an enteric coating.    -   20) The composition of any of embodiments 16-19 and 21 further        comprising one or more of a glidant, disintegrant and filler        (also known as a diluent), where starch may optionally serve in        one or more of these capacities.    -   21) The composition of any of embodiments 16-20 further        comprising cellulose, where for example, the cellulose may        function as a filler and/or a disintegrant in the composition.    -   22) An oral dosage form comprising a pharmaceutically effective        amount of a salt of a cationic protonated polyamine        pharmaceutical agent and an anionic hydrophobic carboxylate.    -   23) The dosage form of any of embodiments 22 and 24-26        comprising from 1.0 to 500 milligrams of the salt.    -   24) The dosage form of any of embodiments 22-23 and 25-26 in a        solid form.    -   25) The dosage form of any of embodiments 22-24 and 26 further        comprising a solid excipient.    -   26) The dosage form of any of embodiments 22-25 having a weight        of 50 mg to 1,000 mg.    -   27) A method of preparing a pharmaceutical formulation for oral        administration, where the formulation comprises a plurality of        inert ingredients, the method comprising combining a salt of a        cationic protonated polyamine pharmaceutical and an anionic        hydrophobic carboxylate with at least one of the plurality of        inert ingredients to form a precursor composition.    -   28) The method of any of embodiments 27 and 29-30 further        comprising isolating an amount of from 1.0 to 1,000 mg of the        precursor composition so as to provide a suitable amount for        formation of an oral dosage form.    -   29) The method of any of embodiments 27-28 and 30 further        comprising isolating a suitable amount from the precursor        composition, and compacting the suitable amount to form a        compressed solid dosage form.    -   30) The method of any of embodiments 27-29 further comprising        isolating a suitable amount from the precursor composition,        compacting the suitable amount to form a compressed solid dosage        form, and placing an enteric coating on the compressed solid        dosage form.    -   31) A method of treatment comprising administering to a subject        in need thereof, a therapeutically effective amount of        pharmaceutical composition comprising a salt of a cationic        protonated polyamine pharmaceutical and an anionic hydrophobic        carboxylate.    -   32) The method of any of embodiments 31 and 33-34 wherein the        pharmaceutical composition is administered in a solid dosage        form to the subject.    -   33) The method of any of embodiments 31-32 and 34 wherein the        subject is being treated for cancer.    -   34) The method of any of embodiments 31-33 wherein the salt is        administered in conjunction with the administration of        difluoromethylornithine (DFMO) to the patient.    -   35) AMXT 1501 dicaprate, e.g., being a salt formed from        components having molecular formulae and structures shown below:

-   -   36) AMXT 1569 dicaprate, e.g., being a salt formed from        components having molecular formulae and structures shown below:

-   -   37) AMXT 2030 dicaprate, e.g., being a salt formed from        components having molecular formulae and structures shown below:

-   -   38) AMXT 1426 dicaprate, e.g., being a salt formed from        components having molecular formulae and structures shown below:

-   -   39) Spermidine dicaprate, e.g., being a salt formed from        components having the molecular formulae and structures shown        below:

-   -   40) A process for preparing a salt, the process comprising        combining an uncharged polyamine pharmaceutical with an        uncharged hydrophobic carboxylic acid in a solvent such as        methanol under proton transfer conditions to form a solution of        a salt of a charged polyamine pharmaceutical and a charged        hydrophobic carboxylate, where the process further comprises        adding a non-solvent such as acetonitrile to the solution and        forming a precipitate comprising the salt.

As some specific embodiments, the present disclosure provides a salt ofa cationic protonated polyamine pharmaceutical agent and an anionic formof a hydrophobic carboxylic acid, wherein the anionic hydrophobiccarboxylic acid is a carboxylate form of a fatty acid selected fromoctanoic acid, decanoic acid, dodecanoic acid and tetradecanoic acid;the cationic protonated polyamine pharmaceutical agent is a protonatedform of a therapeutically effective polyamine excluding peptides andproteins; and the cationic protonated polyamine pharmaceutical agent hasfrom 2 to 4 amine groups and at least one of those protonatable aminegroups is protonated to provide the cationic protonated polyaminepharmaceutical agent. Optionally, the salt has two moles of anionichydrophobic carboxylate for each one mole of cationic protonatedpolyamine pharmaceutical agent, e.g., the cationic protonated polyaminepharmaceutical agent is a protonated form of a polyamine of formula (I)and the anionic hydrophobic carboxylate is a carboxylate form of a fattyacid selected from decanoic acid and dodecanoic acid. Optionally, thecationic protonated polyamine pharmaceutical agent is a di-protonatedform of a polyamine of formula AMXT 1501 and the anionic hydrophobiccarboxylate is deprotonated capric acid, and the salt has two moles ofdeprotonated capric acid for each one mole of protonated AMXT 1501. Forinstance, the salt has the structure

Also optionally, the salt is not in admixture with more than 5 wt % ofany other solid or liquid chemical. In addition, the present disclosureprovides a pharmaceutical composition comprising such a salt, where thecomposition may be, e.g., a solid oral dosage form. The presentdisclosure also provides a method of making such a salt, the methodcomprising: combining a polyamine pharmaceutical agent, a hydrophobiccarboxylic acid and a solvent so as to provide a solution; and isolatinga solid residue from the solution, wherein the solid residue comprisesthe salt of interest. Suitable solvents include water, methanol or acombination thereof. Optionally, about 1.8-2.2 moles of hydrophobiccarboxylic acid are combined with each 1.0 mole of polyaminepharmaceutical agent to provide the salt of interest. The solid residuemay be formed by precipitation from the solution. The method may alsoinclude formulating the solid residue or a portion thereof into a soliddosage form pharmaceutical. In addition, the present disclosure providesa method of treating a medical condition, e.g., cancer, comprisingadministering to a subject in need thereof a therapeutically effectiveamount of such a salt, where optionally the therapeutically effectiveamount of the salt is administered to the subject as a solid dosageform.

As mentioned previously, one or more, e.g., any two, three, four, five,etc. of the polyamines of formulae (I)-(IV), 1426, 1501, 1505, 1569,2030, DENSpm, Squalamine, Deoxyspergualin, F14512, Mozobil, Trientine,Gentamicin, Polymyxin B, MGBG, and spermidine are exemplary polyamineswhich in protonated form may be a protonated polyamine pharmaceuticalagent of the present disclosure. Thus, the present disclosure providesthat any one or more of these polyamines may be a polyamine in the abovelisted embodiments. Other molecules having a plurality of amine groupsand suitable biological activity may also be used to provide a PPA ofthe present disclosure.

Thus, in separate and exemplary embodiments, the present disclosureprovides compounds of formula (I):(HCA)₁; compounds of formula(I):(HCA)₂; compounds of formula (I):(HCA)₃; compounds of formula(II):(HCA)₁; compounds of formula (II):(HCA)₂; compounds of formula(II):(HCA)₃; compounds of formula (III):(HCA)₁; compounds of formula(III):(HCA)₂; compounds of formula (III):(HCA)₃; compounds of formula(IV):(HCA)₁; compounds of formula (IV):(HCA)₂; compounds of formula(IV):(HCA)₃; AMXT 1426:(HCA)₁; AMXT 1426:(HCA)₂; AMXT 1426:(HCA)₃; AMXT1501:(HCA)₁; AMXT 1501:(HCA)₂; AMXT 1501:(HCA)₃; AMXT 1505:(HCA)₁; AMXT1505:(HCA)₂; AMXT 1505:(HCA)₃; AMXT 1569:(HCA)₁; AMXT 1569:(HCA)₂; AMXT1569:(HCA)₃; AMXT 2030:(HCA)₁; AMXT 2030:(HCA)₂; AMXT 2030:(HCA)₃;DENSpm:(HCA)₁; DENSpm:(HCA)₂; DENSpm:(HCA)₃; Squalamine:(HCA)₁;Squalamine:(HCA)₂; Squalamine:(HCA)₃; Deoxyspergualin:(HCA)₁;Deoxyspergualin:(HCA)₂; Deoxyspergualin:(HCA)₃; F14512:(HCA)₁;F14512:(HCA)₂; F14512:(HCA)₃; Mozobil:(HCA)₁; Mozobil:(HCA)₂;Mozobil:(HCA)₃; Trientine:(HCA)₁; Trientine:(HCA)₂; Trientine:(HCA)₃;Gentamicin:(HCA)₁; Gentamicin:(HCA)₂; Gentamicin:(HCA)₃; PolymyxinB:(HCA)₁; Polymyxin B:(HCA)₂; Polymyxin B:(HCA)₃; spermine:(HCA)₁;spermine:(HCA)₂; spermine:(HCA)₃; spermidine:(HCA)₁; spermidine:(HCA)₂;spermidine:(HCA)₃; MGBG:(HCA)₁; MGBG:(HCA)₂; and MGBG:(HCA)₃. In each ofthese embodiments, HCA may be a hydrophobic carboxylic acid as describedherein, e.g., a C₁₀-14 fatty acid such as capric acid.

It is to be understood that the terminology used herein is for thepurpose of describing specific embodiments only and is not intended tobe limiting. It is further to be understood that unless specificallydefined herein, the terminology used herein is to be given itstraditional meaning as known in the relevant art.

As used in this specification and the appended claims, the singularforms “a,” “an,” and “the” include plural referents, i.e., one or more,unless the content and context clearly dictates otherwise. It shouldalso be noted that the conjunctive terms, “and” and “or” are generallyemployed in the broadest sense to include “and/or” unless the contentand context clearly dictates inclusivity or exclusivity as the case maybe. Thus, the use of the alternative (e.g., “or”) should be understoodto mean either one, both, or any combination thereof of thealternatives. In addition, the composition of “and” and “or” whenrecited herein as “and/or” is intended to encompass an embodiment thatincludes all of the associated items or ideas and one or more otheralternative embodiments that include fewer than all of the associateditems or ideas.

Unless the context requires otherwise, throughout the specification andclaims that follow, the word “comprise” and synonyms and variantsthereof such as “have” and “include”, as well as variations thereof suchas “comprises” and “comprising” are to be construed in an open,inclusive sense, e.g., “including, but not limited to.” The term“consisting essentially of” limits the scope of a claim to the specifiedmaterials or steps, or to those that do not materially affect the basicand novel characteristics of the claimed invention.

As described herein, for simplicity, a patient, clinician, or anotherhuman may in some cases be described in the context of the male gender.It is understood that a medical practitioner can be of any gender, andthe terms “he,” “his,” “himself,” and the like as used herein are to beinterpreted broadly inclusive of all known gender definitions.

Any headings used within this document are only being utilized toexpedite its review by the reader, and should not be construed aslimiting the invention or claims in any manner. Thus, the headings andAbstract of the Disclosure provided herein are for convenience only anddo not interpret the scope or meaning of the embodiments.

In the foregoing description, certain specific details are set forth toprovide a thorough understanding of various disclosed embodiments.However, one skilled in the relevant art will recognize that embodimentsmay be practiced without one or more of these specific details, or withother methods, components, materials, etc.

The Examples and preparations provided below further illustrate andexemplify the subject matters of the present invention and methods ofpreparing such subject matter. It is to be understood that the scope ofthe present invention is not limited in any way by the scope of thefollowing Examples and preparations. In the following Examples,molecules with a single chiral center, unless otherwise noted, exist asa racemic mixture. Those molecules with two or more chiral centers,unless otherwise noted, can exist as a racemic mixture of diastereomers.Single enantiomers/diastereomers may be obtained by methods known tothose skilled in the art. The starting materials and various reactantsutilized or referenced in the examples may be obtained from commercialsources, or are readily prepared from commercially available organiccompounds, using methods well-known to one skilled in the art.

EXAMPLES Example 1 Preparation of Free Base Form of AMXT 1501

A 2 L round-bottomed flask was charged with 724.2 g of Amberlyst™ A25hydroxide anion-exchange resin (Dow Chemical, Midland, Mich., USA) and 1liter of methanol. The mixture was stirred with a magnetic stir bar atambient temperature for about 10 minutes, and then the resin wasfiltered using a Büchner funnel. The cleaned resin was transferred intoa beaker until it was ready for use. A clean 2 L round-bottomed flaskwas charged with 57.9 g (81.0 mmole) of the hydrochloride salt of AMXT1501 (Aminex Therapeutics, Inc., Kirkland, Wash., USA) and 2 liters ofmethanol. The mixture was stirred with a magnetic stir bar at ambienttemperature for about 1 hour to yield a turbid solution. The turbidsolution was transferred to a 5 L vessel and the washed Amberlyst™ A25resin was added. The mixture was stirred for 10 minutes at ambienttemperature, during which time the solution became milky white and thenbecame clear. After an additional 10-20 minutes of stirring, the mixtureis filtered to collect the resin. The resin was washed several timeswith a total of about 1 liter of methanol. The filtrate and washingswere combined to provide about 3.1 liter of solution. The solution wasplaced on a roto-evaporator under reduced pressure and the solvent wasremoved at about 30° C. to leave behind a white solid. Additional dryingunder full dynamic vacuum provided 42.18 g (91.5% yield) of dry whitesolid as the free base form of AMXT 1501, which was scraped from thevessel.

Example 2 Preparation of AMXT 1501 Dicaprate Salt

A 250 ml flask was charged with 10 g (17.6 mmole) of AMXT 1501 free baseas prepared in Example 1, 6.0 g (34.8 mmole, 2.0 eq.) of capric acid(Aldrich Chemicals) and 100 ml of methanol. The mixture was stirred witha magnetic spin bar at ambient temperature for about 5 minutes until ahomogeneous solution formed. The solution was stirred for an additional30 minutes, then the stirring was stopped and the solvent was evaporatedunder reduced pressure at 30° C. to provide an off-white solid residue.This residue was dried under full dynamic vacuum for 12-15 hours atambient temperature and then scrapped out of the reaction flask toprovide the titled salt in about 97% yield.

The titled salt was characterized by elemental analysis, and matched thetheoretical with the inclusion of ½ mole of water (H₂O). Elementalanalysis calculated for C₅₂H₁₁₀N₆O₇+½ H₂O═C, 67.49; H, 11.91; N, 9.08;O, 11.52. Found C, 67.65; H, 11.85; N, 8.75; O, 11.58. Karl Fischerwater titration showed 1.3% H₂O associated with the titled salt. Themolecular weight ratio of ½ H₂O to AMXT 1501dicaprate=9.2/913.47=0.986%. Thermogravimetric analysis (TGA) showed theloss of 1.073% weight at 100 to 135° C.

Differential Scanning calorimetry (DSC) was performed on the titledsalt, resulting in the DSC scan shown in FIG. 2 and theThermogravimetric Analysis (TGA) scan shown in FIG. 3.

As another option, a non-solvent can be added to a solution formed uponmixing the free base form of a polyamine (e.g., the free base form ofAMXT 1501) and a hydrophobic carboxylic acid (e.g., two molarequivalents of capric acid) in a solvent which dissolves the resultingsalt. The addition of the non-solvent will cause a precipitation of theresulting salt, where the precipitate may be separated from thenon-solvent by, e.g., decantation or filtration. This method isexemplified by the following method. To a clear solution formed bydissolving 283.2 g of AMXT 1501 free base in 455 mL methanol is added171.5 g of capric acid (2 equivalents), resulting in an approximate 1g/mL solution of salt composition. This solution is cooled in an icebath and 3.7 L of acetonitrile is added slowly to the solution over a 1to 2 hour period. When about 30% of the total acetonitrile charge hasbeen added, the solution becomes cloudy, followed by the precipitationof a white solid product. The resulting thick slurry is filtered and theresulting white powder is washed with acetonitrile and dried overnightto give 403.9 g (79%) of AMXT 1501 dicaprate as a white powder.

Example 3 Tablet of AMXT 1501 Dicaprate Salt

A 200 ml round-bottomed flask was charged with 38.4 g of the dicapricsalt of AMXT 1501 from Example 2, 28.5 g of Starcap™ 1500 starch(Colorcon, Harleysville, Pa., USA), 8.4 g of sodium cross carmellose(FMC, Philadelphia, Pa., USA), 42.3 g Avicel™ PH-102 microcrystallinecellulose (FMC, Philadelphia, Pa., USA) and 1.2 g Aerosil™ R202 fumedsilica (Evonik Corp., Piscataway, N.J., USA). This mixture was brisklyshaken for a few seconds, then it was placed on a roller assembly wherethe blend was rolled at high speed for 30 minutes. After this rollingwas completed, 1.2 g of magnesium stearate (Spectrum Chemicals, Tucson,Ariz., USA) was added and the mixture shaken briskly for a few secondsfollowed by rolling for one minute. The rolled mixture was then loadedinto the feeder of a tablet press and pressed into the form of a tabletby applying a pressure of about 1.5 tons. The tablet size was 10 mmhexagon shape and the average weight per tablet was 0.4 g. The tabletshad a hardness of 18-20 kp, a disintegration time of less than 15minutes.

Example 4 Enterically Coated Tablet of Capric Salt of AMXT 1501

A tared 500 ml beaker was equipped with an overhead stirrer and wascharged with 340 g of distilled water. The water was stirred until avortex appeared. To the rapidly stirring water was added 40 g of Opadry™hydroxyl propylmethyl cellulose (HPMC, Colorcon) over a period of about2 minutes. Stirring was continued for about 1 hour, during which time ahomogeneous semi-viscous opaque solution formed. Water (60 g) was thenadded with stirring, followed by an additional 60 minutes of stirring.No particles or agglomerated solids were visible. The stirring wasstopped and the beaker and contents were refrigerated at 5° C. overnightto provide the clear coat coating solution.

A tared 2 L beaker equipped with an overhead stirrer was charged with600 g of distilled water. The water was stirred until a vortex formed.To this rapidly stirring water was added 200 g of Acryl-EZE™ entericcoating (Colorcon) over a period of about 2 minutes, followed by 60minutes of additional stirring to provide a homogenous white suspension.To the white suspension was added 200 g of water followed by 5 minutesof additional stirring. The suspension was then left overnight at 5° C.Prior to use, the suspension was removed from the refrigerator andallowed to warm up to room temperature so as to provide the Acryl-EZEenteric coating solution.

A Freund Hi-Coater Model HCT-30 with a Freund spray nozzle was used toprepare the enterically coated tables. 500 g of placebo tablets wereplaced on the pan of the Freund coater, and the heater and fan of thecoater were turned on. The coater was set at an intake temperature of88° C., a bed temperature of 37.5° C., and a pan rotation speed of 14rpm. After these conditions were met, which took 20-30 minutes, 94.7 gof tablets (about 234 tablets of different shape than the placebotablets above) of the dicapric salt of AMXT 1501 as prepared in Example3 were added to the pan. Onto the rotating and cascading tablets in thepan, the clear coat solution (HPMC) was sprayed at a pressure of 1.2kg/cm³ and a rate of 2.0 g/min for a first 20 minutes. After this first20 minutes, the spray rate was increased to 2.6 g/min. Spraying wascontinued until an average tablet weight gain of 2% solids, at whichpoint the spraying was discontinued and rolling and heating weremaintained for about 2 minutes. About 111 g of clear coat solution wasused. The resulting tablet mixture were white with a slight shine.

These white, slightly shiny tablets were then exposed to the entericcoating solution (Acryl-EZE enteric coating). The coater was primed withthe enteric coating solution, then set to achieve an intake temperatureof 88° C. and a bed temperature of 38° C. When these conditions weremet, the pan was made to rotate at 14 rpm. To the rotating tablets wassprayed the enteric coating solution at a pressure of 1.2 kg/cm³ and arate of 2.6 g/min. Spraying was continued until an average weight gainof 8-10% solids was achieved. About 665 g of enteric coating solutionwas used to provide 234 enterically coated tablets of the capric salt ofAMXT 1501 following separation from the placebo tablets.

Example 5 Solubility Analysis of AMXT 1501 Dicaprate Salt

Twenty-three 2 ml centrifuge tubes with caps were each charged with atleast 10 mg of the dicapric salt of AMXT 1501 as prepared in Example 2.Each vial was labeled with a test solvent as identified in the Table.After labeling, to each vial was added 2.0 ml of the indicated solvent,with the exception of the lanolin alcohol labeled vial, which received1.8 g of solid lanolin alcohol.

After addition of the solvents was completed, the vials were sonicatedin a sonication bath set at 45° C. for about 60 minutes. The vialcontaining lanolin alcohol was placed in a hot water bath set at 85° C.and heated in this bath for about 30 minutes prior to being placed inthe sonicator. After heating for about 60 minutes, all samples wereremoved from the heat sources and permitted to cool to ambienttemperature over a period of one hour.

After cooling, the samples were prepared for analysis by firstcentrifuging the samples in the vials. After centrifugation, the sampleswere diluted 1 to 10 in an HPLC vial with 0.1% trifluoroacetic acid(TFA) in acetonitrile. In some cases, an additional 1 to 10 dilution wasneeded if the HPLC response was off scale. The results of the solubilityanalysis are shown in Table 1.

TABLE 1 Test Solvent Solubility Distilled water ≥10 mg/ml* Aq. HCl, pH 3≥10 mg/ml* Ethanol ≥10 mg/ml* Methanol ≥10 mg/ml* Isopropyl alcohol ≥10mg/ml* Glycerol ≥10 mg/ml* Propylene glycol ≥10 mg/ml* TWEEN 20 ≥10mg/ml* TWEEN 80 ≥10 mg/ml* PEG 400 ≥10 mg/ml* Dimethyl formamide ≥10mg/ml* Dimethyl sulfoxide ≥10 mg/ml* Tetrahydrofuran ≥10 mg/ml* Diethylglycol MME ≥10 mg/ml* Hexane Not soluble Methylene chloride ≥10 mg/ml*Ethyl acetate 0.68 mg/ml Toluene 2.6 mg/ml Vitamin E oil ≥10 mg/ml*Lanolin alcohol ≥10 mg/ml* Lecithin ≥10 mg/ml* Isopropyl myristateReacted with API

Longer-term solubility was determined by evaluating the samples 24 hoursafter preparation. The results from the longer-term study are providedin Table 2.

TABLE 2 Test Solvent Solubility Distilled water ≥10 mg/ml* Aq. HCl, pH 3≥10 mg/ml* Ethanol ≥10 mg/ml* Methanol ≥10 mg/ml* Isopropyl alcohol ≥10mg/ml* Glycerol ≥10 mg/ml* Propylene glycol ≥10 mg/ml* TWEEN 20 ≥10mg/ml* TWEEN 80 ≥10 mg/ml* PEG 400 ≥10 mg/ml* Dimethyl formamide ≥10mg/ml* Dimethyl sulfoxide ≥10 mg/ml* Tetrahydrofuran ≥10 mg/ml* Diethylglycol MME ≥10 mg/ml* Hexane Not soluble Methylene chloride ≥10 mg/ml*Ethyl acetate 0.62 mg/ml Toluene 2.7 mg/ml Vitamin E oil ≥10 mg/ml*Lanolin alcohol ≥10 mg/ml* Lecithin ≥10 mg/ml* Isopropyl myristateReacted with API

The capric acid salt prepared in Example 2 had a solubility of greaterthan 10 mg/ml in most of the solvents tested. The lowest solubility wasfound in hexane where by HPLC analysis no material was detected. Thecapric acid salt also had low solubility in ethyl acetate and toluene.

Example 6 Preparation and Characterization of the Mono-, Di-, Tri- andTetra-Caprate Salt Forms of AMXT 1501

A 50 gram sample of AMXT 1501 4HCl salt was converted in methanol to thefree base using Dow Amberlyst™ A26 OH resin as described in Example 1.The solvent was removed on the rotovap to give the free base as a solidin an 88% yield. The free base was analyzed by HPLC to give an assay of97% using the HCl salt as a reference and correcting for the molecularweight.

To prepare the 1, 2, 3, and 4× salts, 5 grams of the free base above andthe appropriate amount of capric acid was combined and dissolved inmethanol. The methanol from each salt was removed using the rotoryevaporator. The resulting solids were dried in the vacuum oven at roomtemperature.

Solubility. During the preparation section above, it was observed whenthe residue in the round bottom from each of the salts was washed outthere was a clear progression of the mono- and dicaprate salts beingmuch more water soluble than the tri- and tetra-AMXT 1501 caprate salts.To test the solubility, a known portion of each salt was added to 1 mlof DI water. The solutions were vortexed and sonicated sometimes severaltimes and observed for solubility. In addition to the 4 salts that wereprepared in the same manner and at the same time, a sample of the 2×caprate salt with AMXT 1501 that was precipitated from methanol usingacetonitrile was also evaluated to determine if there was any observedsolubility differences between this 2× salt and the one isolated througha simple removal of the methanol solvent. The results are summarized inTable 3. The mono- and di-caprate salts showed a significantly highersolubility in water than the tri- and tetra-caprate salts.

TABLE 3 Solubility of various ratios of AMXT 1501 Caprate Salts in H₂OSample Salt Ratio Solubility Monocaprate 1x >150 mg/ml Dicaprate 2x >150mg/ml Tricaprate 3x  <10 mg/ml Tetracaprate 4x  <10 mg/ml Dicaprate(Isolated 2x >150 mg/ml from MeOH/ACN)

TGA Analysis. Five AMXT 1501 capric salt ratio samples were analyzed byTGA and heated at a rate of 20° C. per minutes to a final temperature of400′C. The TGAs were processed by first showing the percent weight dropfrom the starting point to 100° C., which could give an indication ofthe water content, and then the weight drop to the first plateau. Table4 shows the data for each sample.

TABLE 4 TGA of AMXT 1501 Capric Salts Capric % loss to % loss to nextplateau Sample Salt 100° C. (temperature of plateau) Monocaprate 1x0.3038% 18.56% (250° C.) Dicaprate 2x 0.6179% 32.40% (288° C.)Tricaprate 3x 0.2165% 38.36% (275° C.) Tetracaprate 4x 0.1496% 42.41%(275° C.) Dicaprate (isolated 2x 0.8699% 30.98% (288° C.) from MeOH/ACN)

DSC Analysis. The salt ratio samples that were analyzed above by TGAwere also analyzed by DSC. All of the samples were heated at a rate of20° C./minute up to a final temperature of 200° C. The DSC analysislooked for the presence of any glass transitions, melting points and themelting point range at half height to determine purity of the sample.Target range of half height is about 5° C. Table 5 shows the meltingpoints of the sample and melting range at half height. There were noobserved glass transitions for any of the samples.

TABLE 5 DSC of Capric Salts Capric Melting Melting range Sample SaltPoint at half height Monocaprate 1x 83.75° C. 4.92° C. Dicaprate 2x59.19° C.  3.98° C.* Tricaprate 3x 56.99° C. 5.56° C. Tetracaprate 4x58.87° C. 3.91° C. Dicaprate (Isolated 2x 61.59° C. 7.17° C. fromMeOH/ACN) *This sample had at least one more melting point at 72.31° C.

Characterization of the salts by FT-IR. The same samples above wereanalyzed by FT-IR using a diamond ATR sampling unit. Table 6 lists someof the bands that are present in all of the IR scans. The overallsignals appear to become weaker as capric substitution increases.

TABLE 6 FT-IR Analysis Characteristics of AMXT 1501 Caprate Salts Cm⁻¹Description 1550-1650 Carboxylate ion and amides (capric and AMXT 1501)3000-2840 CH bands from normal alkanes (capric and AMXT 1501) 3330-3060NH bands and amine salts (AMXT 1501)

Determination of residual water by KF. The water content of the sampleswas determined by KF titration. Table 7 shows the average water contentand the number of samples used for the average.

TABLE 7 Water Content of AMXT 1501 Caprate Salt Samples Percent water(Number of Sample Capric Salt runs used for average) Monocaprate 1x0.51% (4) Dicaprate 2x 0.68% (3) Tricaprate 3x 0.47% (2) Tetracaprate 4x0.23% (2) Dicaprate (Isolated 2x 1.05% (2) from MeOH/ACN)

Elemental Analysis. The four samples prepared were sent for C, H, N andO analysis. The theory percentage of the elements were determined usingthe following formulas shown in Table 8. The calculated and found valuesare shown below in Tables 9 to 12. Variability in the results from thecalculated and found are likely due to hydrates or a slight variation inthe equivalents of the capric acid that was added to the free base toproduce each salt substitution. As capric acid to AMXT 1501 free baseratio increases water solubility decreases. The mono- and dicaprate AMXT1501 salts showed good solubility at a concentration of >150 mg/mlwhereas the solubility of the tri- and tetracaprate AMXT 1501 salts werevery low at <10 mg/ml.

TABLE 8 Theoretical Formulas for AMXT 1501 Capric Salts Sample CapricSalt Theory Formula Monocaprate 1x C₄₂H₈₈N₆O₄ Dicaprate 2x C₅₂H₁₀₈N₆O₆Tricaprate 3x C₆₂H₁₂₈N₆O₈ Tetracaprate 4x C₇₂H₁₄₈N₆O₁₀

TABLE 9 Elemental Analysis for AMXT 1501 Monocaprate Salt MonocaprateCalculated Found (% Difference) Carbon 68.1% 67.60% (0.5%)  Hydrogen12.0% 11.22% (0.78)  Nitrogen 11.3% 11.33% (0.03%) Oxygen 8.6%  8.66%(0.06%)

TABLE 10 Elemental Analysis for AMXT 1501 Dicaprate Salt DicaprateCalculated Found (% Difference) Carbon 68.4% 67.94% (0.46%) Hydrogen11.9% 12.07% (0.17%) Nitrogen 9.2%  9.13% (0.07%) Oxygen 10.5% 11.17%(0.67%)

TABLE 11 Elemental Analysis for AMXT 1501 Tricaprate Salt TricaprateCalculated Found (% Difference) Carbon 68.6% 68.42% (0.18%) Hydrogen11.9% 11.79% (0.11%) Nitrogen 7.7%  7.78% (0.08%) Oxygen 11.8% 12.38%(0.58%)

TABLE 12 Elemental Analysis for AMXT 1501 Tetracaprate Salt TetracaprateCalculated Found (% Difference) Carbon 68.7% 69.26% (0.56%) Hydrogen11.9% 12.31% (0.41%) Nitrogen 6.7%  6.82% (0.12%) Oxygen 12.7% 13.03%(0.33%)

Using TGA analysis, all salts showed various amounts of weight loss upto 100° C. likely due to different amounts of water of hydrations. Thenext plateau of weight loss to approximately the same final temperatureshowed an increase in weight loss as substitution increased which islikely due to loss of the capric salt substitution as the sample isheated. The DSC analysis showed no definitive glass transition pointssuggesting that the materials are mostly crystalline. The melting pointof the mono-caprate AMXT 1501 salt was the highest, and the di-, tri-and tetra-caprate AMXT 1501 salts were lower with approximately the samemelting point. All of the samples gave the same characteristic bands forthe functional groups by FT-IR, however the bands appear to be weaker asthe capric acid to AMXT 1501 ratio increases. Water analysis by KarlFischer titration showed the highest water content with the mono- anddicaprate AMXT 1501 salts and a lower water content with the tri- andtetra-AMXT 1501 salts. Elemental analysis shows reasonable agreementwith theory and follows the theory trends for C, H, N and O analysis.

Example 7 Pharmacokinetic Analysis of Various AMXT 1501 HCA SaltsDelivered Orally in Beagle Dogs

Following an acclimation of five (5) days, 12 beagle dogs were dividedinto four groups of three dogs per group, and were dosed with twotablets with the assigned compound or salt. Following doseadministration all the animals had serial blood collections. Theexperimental design for the study is provided in Table 13.

TABLE 13 Experimental Study Design Animals per Dose AMXT 1501 1501 DoseLevel 1501 Dose Conc. Dose Volume Group Group Route Salt Form mg/kgmg/tablet No. of Tablets 1 3 (1M/2F) PO Free base 16.0 80 2 2 3 (2M/1F)PO Dicholate 16.0 80 2 3 3 (1M/2F) PO Phosphate 16.0 80 2 4 3 (2M/1F) PODicaprate 16.0 80 2

Tablet formulation information is provided in Tables 14, 15, 16 and 17.

TABLE 14 Formulation for AMXT 1501 Free Base Excipient Name Weight %Weight (mg) AMXT 1501 Free Base 20.00 80.0 Starch 1500 28.50 114.0 CrossCarmelose 7.00 28.0 Microcrystalline cellulose (Avicel PH 102) 42.50170.0 Fumed Silica 1.00 4.0 Magnesium Stearate 1.00 4.0 Total 100.00400.0

TABLE 15 Formulation for AMXT 1501 Dicholate Salt Excipient Name Weight% Weight (mg) AMXT 1501 Cholate Salt (58.2% active) 34.38 137.5Phospholipon 90H 2.50 10.0 Starch 1500 21.63 86.5 Cross Carmelose 7.0028.0 Microcrystalline cellulose (Avicel PH 102) 32.50 130.0 Fumed Silica1.00 4.0 Magnesium Stearate 1.00 4.0 Total 100.00 400.0

TABLE 16 Formulation for AMXT 1501 Phosphate Salt Excipient Name Weight% Weight (mg) AMXT 1501 Phosphate Salt (74.7% Active) 26.78 107.1 Starch1500 25.48 101.9 Cross Carmelose 7.00 28.0 Microcrystalline cellulose(Avicel PH 102) 38.75 155.0 Fumed Silica 1.00 4.0 Magnesium Stearate1.00 4.0 Total 100.00 400.0

TABLE 17 Formulation for AMXT Dicaprate Salt Excipient Name Weight %Weight (mg) AMXT 1501 2x Capric Salt (62.5% Active) 32.00 128.0 Starch1500 23.75 95.0 Cross Carmelose 7.00 28.0 Microcrystalline cellulose(Avicel PH 102) 35.25 141.0 Fumed Silica 1.00 4.0 Magnesium Stearate1.00 4.0 Total 100.00 400.0

Table 18 provides pharmacokinetic data obtained using the various saltforms of AMXT 1501 following single PO dosing to dogs. In Table 18,Group 1 received the free base form of AMXT 1501, Group 2 received thedicholate salt of AMXT 1501, Group 3 received the phosphate salt form ofAMXT 1501, and Group 4 received the dicaprate salt form of AMXT 1501.Also in Table 18, T_(max) is reported in units of hour, where T_(max) isdefined as the time after dosing at which the maximum plasmaconcentration of AMXT 1501 is reached, C_(max) is reported in units ofng/mL, where C_(max) is defined as the maximum concentration of AMXT1501 observed in the plasma, AUC_(0-t) is reported in units ofhour*ng/mL, and is defined as the area under the curve in a graph ofplasma concentration as a function of time to the time of 24 hours(i.e., t=24 hours), and t_(1/2) is reported in units of hour, wheret_(1/2) is defined as the time after dosing at which the plasmaconcentration of AMXT 1501 reaches half of its maximum concentration. InTable 18, SD refers to standard deviation and CV % refers to coefficientof variability.

TABLE 18 Pharmacokinetic Data Group ID Parameter N Mean SD Min MedianMax CV % Group 1 T_(max) 3 8.00 3.46 6.00 6.00 12.0 43.3 C_(max) 3 250218 31.3 250 468 87.4 AUC_(0-t) 3 4710 4080 363 5330 8450 86.5 t_(1/2) 19.76 N.D. (n = 1) 9.76 9.76 9.76 N.D. (n = 1) Group 2 T_(max) 3 6.000.00 6.00 6.00 6.00 0.0 C_(max) 3 297 154 182 237 472 51.9 AUC_(0-t) 36650 3160 4780 4870 10300 47.5 t_(1/2) 3 13.2 0.822 12.2 13.6 13.7 6.2Group 3 T_(max) 3 6.00 0.00 6.00 6.00 6.00 0.0 C_(max) 3 115 115 19.582.8 242 99.9 AUC_(0-t) 3 3280 4320 256 1350 8230 131.8 t_(1/2) 2 15.512.6 6.57 15.5 24.4 81.3 Group 4 T_(max) 3 6.00 0.00 6.00 6.00 6.00 0.0C_(max) 3 276 74.0 201 278 349 26.8 AUC_(0-t) 3 6580 1980 4710 6370 864030.0 T_(1/2) 3 14.0 1.98 12.4 13.4 16.2 14.2

Results from this study are shown in the Figures, where FIGS. 4A, 4B, 4Cand 4D show plasma levels obtained following single oral dosing ofeither AMXT 1501 free base or various salt forms of AMXT 1501 formulatedin enterically coated tablets delivered to dogs. The data from Group 1is shown in FIG. 4A, which shows plasma levels obtained following dosingof the free base form of AMXT 1501 and resulted in highly variableamounts of plasma AMXT 1501 obtained. Circle and square data points arefrom female dogs and the triangle data points are from a male dog.Higher plasma levels were obtained using the dicholate salt of AMXT 1501following single oral dosing shown in FIG. 4B, which shows the data fromGroup 2 where the circle data points are from a female dog and thesquare and triangle data points are from male dogs. These results wereconsistent with the levels obtained using the dicaprate salt form ofAMXT 1501 as determined from Group 4 animals and plotted in FIG. 4D,where circle data points are from a female dog and the square andrectangle data points are from male dogs. Plasma levels observedfollowing oral dosing of the phosphate salt of AMXT 1501, i.e., theGroup 3 animals, are plotted in FIG. 4C where circle and square datapoints are from female dogs and triangle data points are from a maledog, and again were highly variable and comparable to results obtainedusing the free base of AMXT 1501 (FIG. 4A). These results highlight theimportance of the salt counterion and support use of lipophilic acids asthe counterion in order to achieve, e.g., consistent sustained plasmalevels of polyamine pharmaceuticals followed oral dosing.

FIGS. 5A, 5B, 5C and 5D shows average plasma AMXT 1501 levels obtainedusing the various compounds described in Table 13 following single oraldelivery to Groups 1, 2, 3 and 4 of dogs. Average levels of AMXT 1501are graphed in FIGS. 5A, 5B, 5C and 5D showing the standard deviation inthe data, and highlight the variable drug levels observed using the freebase and phosphate salt forms of AMXT 1501 (Group 1, FIG. 5A and Group3, FIG. 5C, respectively) and the much more consistent inter-animalblood levels of AMXT 1501 obtained using the dicholate and dicaprateforms of AMXT 1501 (Group 2, FIG. 5B and Group 4, FIG. 5D,respectively). The dicholate and dicaprate salts, which are formed fromrepresentative hydrophobic carboxylic acids cholic acid and capric acidas disclosed herein, thus provide improved bioavailability compared tothe free base or phosphate salt, in that the cholate and caprate saltsdo not show as much subject-to-subject variability when administered totest animals.

Example 8 5 Day Dog Repeat Oral Dosing with AMXT 1501 Dicaprate

The objectives of this portion of the study were to assess thepharmacokinetics (PK) of the dicaprate salt form of AMXT 1501 whenadministered via oral (PO) enterically-coated tablet administration tomale and female beagle dogs across a range of dose levels and to compareAMXT 1501 dicaprate salt PK when administered withdifluoromethylornithine (DFMO) compared to AMXT 1501 dicaprate saltalone, and to compare exposure after single and repeat AMXT 1501dicaprate dosing. Male and female beagle dogs (N=1 or 2 males and 1 or 2females, for a total of N=3 per group) were administered five daily oral(PO) tablet doses of the dicaprate salt form of AMXT 1501. AMXT 1501dicaprate salt was administered as monotherapy at 8, 16, or 32 mg/kg, orat 16 mg/kg in combination with 200 mg/kg PO difluoromethylornithine(DFMO). The pharmacokinetic (PK) profiles after dosing on Days 1 and 5were evaluated using standard noncompartmental methods.

Following single or repeat once daily PO dosing of 8, 16, or 32 mg/kg ofthe dicaprate salt form of AMXT 1501 to male and female beagle dogs,concentrations were measured out to 24 hr. postdose (the last measurabletime point). The AMXT 1501 T_(max) was observed at 4 to 12 hr. postdose,and exposure based on C_(max) and AUC_(0-t) increased in adose-dependent manner. In the animals where it could be estimated, themean Day 1 t_(1/2) values ranged from 7.99 to 23.2 hr. and the mean Day5 t_(1/2) values ranged from 8.69 to 20.8 hr.

The following experimental design was used. Beagle dogs, 1 or 2 malesand 1 or 2 females for a total of 3 dogs per group, were randomlyassigned to the four treatment groups as outlined in Table 19.

TABLE 19 Study Design Nominal PK Group AMXT 1501 Dose Sampling No.(mg/kg/day)^(a) Treatment Time Points 1 8 AMXT 1501 dicaprate 0.5, 1, 2,4, 8, 2 16 AMXT 1501 dicaprate 12, and 24 hr. 3 32 AMXT 1501 dicaprate 416 AMXT 1501 dicaprate + DFMO^(b) ^(a)The AMXT 1501 dicaprate doses wereadministered as 80 mg (free base amounts) tablets (1, 2, 4, and 2tablets per day in Groups 1, 2, 3, and 4, respectively). ^(b)DFMO wasadministered following the AMXT 1501 dicaprate dose as a 40 mg/mL POgavage with 200 mg/kg delivered.

AMXT 1501 dicaprate salt was administered in tablet form once daily forfive days. After dosing on Days 1 and 5, serial blood samples werecollected from each animal (3 per group) and processed to plasma forAMXT 1501 concentration analyses. Plasma samples were analyzed for AMXT1501 concentration via a liquid chromatography/mass spectrometry(LC/MS-MS) procedure and the resulting concentration versus time datawere used to estimate individual animal PK parameters usingnoncompartmental analysis (NCA).

Table 20 provides summarized AMXT 1501 plasma pharmacokineticsparameters following single (Day 1) or repeat once daily (Day 5) POdosing of AMXT 1501 dicaprate salt to male and female beagle dogs.

TABLE 20 AMXT 1501 Plasma Pharmacokinetics Parameters Following Single(Day 1) or Repeat Once Daily (Day 5) PO Dosing to Male and Female BeagleDogs T_(max) C_(max) AUC_(0-t) t_(1/2) Group Treatment Dose Level StudyDay Animal ID hr. ng/mL hr.*ng/mL hr. 1 AMXT 1501 dicaprate  8 mg/kg 11F1 8.00 139 2010 NC^(a) 1F2 4.00 168 2050 9.30 1M1 NC^(b) NC^(b) NC^(b)NC^(b) Mean 6.00 154 2030 9.30 SD 2.83 20.5 28.3 N/A 1 AMXT 1501dicaprate  8 mg/kg 5 1F1 4.00 405 5530 9.55 1F2 8.00 360 5620 NC^(a) 1M14.00 254 3100 7.82 Mean 5.33 340 4750 8.69 SD 2.31 77.5 1430 1.22 2 AMXT1501 dicaprate 16 mg/kg 1 2F1 4.00 202 3870 36.2 2M1 4.00 262 3190 10.32M2 8.00 249 3300 NC^(a) Mean 5.33 238 3450 23.2 SD 2.31 31.6 364 N/A 2AMXT 1501 dicaprate 16 mg/kg 5 2F1 12.0 523 9410 NC^(a) 2M1 4.00 4546250 11.7 2M2 8.00 714 11000 NC^(a) Mean 8.00 564 8890 11.7 SD 4.00 1352420 N/A 3 AMXT 1501 dicaprate 32 mg/kg 1 3F1 4.00 563 6250 27.1 3F24.00 446 5830 10.0 3M1 8.00 333 4900 NC^(a) Mean 5.33 447 5660 18.6 SD2.31 115 694 N/A 3 AMXT 1501 dicaprate 32 mg/kg 5 3F1 4.00 1140 1680010.7 3F2 8.00 662 11000 NC^(a) 3M1 8.00 708 11100 NC^(a) Mean 6.67 83713000 10.7 SD 2.31 264 3300 N/A 4 AMXT 1501 dicaprate + DFMO 16 mg/kg 14F1 4.00 476 5480 7.99 4M1 8.00 317 5090 NC^(a) 4M2 8.00 204 2980 NC^(a)Mean 6.67 332 4520 7.99 SD 2.31 137 1350 N/A 4 AMXT 1501 dicaprate +DFMO 16 mg/kg 5 4F1 12.0 493 9540 NC^(a) 4M1 4.00 418 7880 20.8 4M2 8.00262 3680 NC^(a) Mean 8.00 391 7030 20.8 SD 4.00 118 3020 N/A N/A: notapplicable (N ≤ 2) ^(a)NC: not calculated (not enough data in theterminal phase of the concentration versus time profile to calculatet_(1/2)) ^(b)NC: not calculated (only one time point with measurableAMXT 1501 concentrations)

Selected results from this study are show in the figures, where FIGS.6A, 6B, 6C and 6D show individual animal AMXT 1501 plasma concentrations(ng/mL) following a single PO dose of the enterically coated AMXT 1501dicaprate tablets to male and female beagle dogs at day 1. FIG. 6A has adose level of 8 mg/kg/day (Group 1; circle and square data points arefrom female dogs while triangle data points are from a male dog), FIG.6B has a dose level of 16 mg/kg/day (Group 2; circle data points arefrom a female dog while square and triangle data points are from maledogs), FIG. 6C has a dose level of 32 mg/kg/day (Group 3; circle andsquare data points are from female dogs while the triangle data pointsare from a male dog), and FIG. 6D has a dose level of 16 mg/kg/day butincludes DFMO in the dose (Group 4; circle data points are from a femaledog while square and triangle data points are from male dogs).

FIGS. 7A, 7B, 7C and 7D show individual animal AMXT 1501 plasmaconcentration (ng/mL) following repeat once daily PO dosing to male andfemale beagle dogs at day 5. FIG. 7A has a dose level of 8 mg/kg/day(Group 1), FIG. 7B has a dose level of 16 mg/kg/day (Group 2), FIG. 7Chas a dose level of 32 mg/kg/day (Group 3), and FIG. 7D has a dose levelof 16 mg/kg/day but includes DFMO in the dose (Group 4).

FIGS. 8A and 8B show mean (±SD) AMXT 1501 plasma concentrations (ng/mL)after single (Day 1; FIG. 8A) or repeat once daily (Day 5; FIG. 8B) POdosing of AMXT 1501 dicaprate monotherapy to male and female beagledogs. The circle data points are from animals receiving 8 mg/kg/day; thesquare data points are from animals receiving 16 mg/kg/day; and thetriangle data points are from animals receiving 32 mg/kg/day.

FIGS. 9A and 9B show mean (±SD) AMXT 1501 plasma concentrations (ng/mL)after single (Day 1; FIG. 9A) or repeat once daily (Day 5; FIG. 9B) POdosing of 16 mg/kg AMXT 1501 dicaprate monotherapy versus 16 mg/kg AMXT1501 dicaprate in combination with DFMO to male and female beagle dogs.In FIG. 9A, square data points are from Group 2 animals who received 16mg/kg/day AMXT 1501 without DFMO while triangle data points are fromGroup 4 animals who received 16 mg/kg/day AMXT 1501 in combination withDFMO. FIG. 9B shows equivalent data from the same set of animals after 5days of daily dosing.

FIGS. 10A, 10B, 10C and 10D show mean (±SD) AMXT 1501 plasmaconcentrations (ng/mL) after single (Day 1) or Repeat Once Daily (Day 5)PO dosing to male and female beagle dogs, Day 1 versus Day 5. In FIG.10A, the square data points are from Group 1 animals who received 8mg/kg/day of AMXT 1501 dicaprate as measured on Day 1, while thetriangle data points are from the same animals receiving the same dailydose but as measured on Day 5. In FIG. 10B, the square data points arefrom Group 2 animals who received 16 mg/kg/day of AMXT 1501 dicaprate asmeasured on Day 1, while the triangle data points are from the sameanimals receiving the same daily dose but as measured on Day 5. In FIG.10C, the square data points are from Group 3 animals who received 32mg/kg/day of AMXT 1501 dicaprate as measured on Day1, while the triangledata points are from the same animals receiving the same daily dose butas measured on Day 5. In FIG. 10D, the square data points are from Group4 animals who received 16 mg/kg/day of AMXT 1501 dicaprate and DFMO asmeasured on Day1, while the triangle data points are from the sameanimals receiving the same daily dose but as measured on Day 5.

These data demonstrate that the tested formulation and delivery methodsprovide sustained and consistent concentrations of AMXT 1501 in theplasma, after single dosing and after repeat dosing.

Example 9 AMXT 1501 Dicaprate PK Evaluation in Beagle Dogs During a28-day Repeat-Dose Toxicity Study

Animals received once daily tablet, oral administration of 8, 16, or 32mg/kg/day dose levels of AMXT 1501 dicaprate tablets without DFMO, or 8or 16 mg/kg/day AMXT 1501 dicaprate salt with DFMO. AMXT 1501 PKparameters were calculated for all AMXT 1501 dicaprate-dosed animals forthe first dose (Day 1) and last dose (Day 28).

AMXT 1501 exposure was maintained over the 24 hour dosing period at alltested dose levels. There was no obvious effect of gender on AMXT 1501T_(max). With the exception of Day 1 exposure in the 8 mg/kg/day AMXT1501 without DFMO dose group, where mean C_(max) and AUC₀₋₂₄ hr wereconsistent between genders, exposure was higher in females than in malesafter single or repeat dosing. After a single (Day 1) dose of AMXT 1501dicaprate with or without DFMO, exposure based on mean C_(max) andAUC_(0-24 hr) increased in a slightly less than dose-proportionalmanner. There was no consistent effect of gender, dose level, or DFMO onAMXT 1501 accumulation. Mean AR_(Cmax) values ranged from 1.62 to 3.63and mean AR_(AUC) values ranged from 1.68 to 3.80. The Day 28 individualanimal AMXT 1501 t_(1/2) values ranged from 8.85 to 69.4 hours andtended to increase with increasing dose. There was no substantial effectof DFMO on single or repeat dose AMXT 1501 levels.

The data from these experiments are provided in FIGS. 11A and 11B whichshow mean (SD) AMXT 1501 plasma concentrations (ng/mL) following single(Day 1, FIG. 11A) or repeat oral dosing (Day 28, FIG. 11B) to male andfemale beagle dogs and AMXT 1501 dicaprate dose level comparison to thesituation where no DFMO was administered (males and females combined).Data is also provides in FIGS. 12A, 12B, 12C, 12C, 12E and 12F whichshow mean (SD) AMXT 1501 plasma concentrations (ng/mL) following single(Day 1) or repeat oral dosing (Day 28) to male and female beagle dogs;males versus females. FIG. 12A shows data for Group 2 (low dose, 8mg/kg/day), Day 1. FIG. 12B shows data for Group 3 (mid dose, 16mg/kg/day), Day 1. FIG. 12C shows data for Group 4 (high dose, 32mg/kg/day), Day 1. FIG. 12D shows data for Group 2 (low dose, 8mg/kg/day), Day 28. FIG. 12E shows data for Group 3 (mid dose, 16mg/kg/day), Day 28. FIG. 12F shows data for Group 4 (high dose, 32mg/kg/day), Day 28, according to a study as described herein.

TABLE 21 Toxicokinetic Parameter Summary Following Repeat Once DailyDosing of AMXT 1501 Dicaprate either Without or With DFMO in Male andFemale Beagle Dogs; Males and Females Combined AMXT 1501 Dose DFMO DoseDosing Parameter Group (mg/kg/day) (mg/kg/day) Day (Units) N Mean SDMin. Median Max. CV % 2 8 0 1 T_(max) (hr.) 9 5.33 3.16 2.00 6.00 12.059.3 C_(max) (ng/mL) 9 95.6 47.2 30.8 115 158 49.4 AUC_(0-24 hr) 9 1330755 374 1500 2810 56.5 (hr.*ng/mL) 2 8 0 28 T_(max) (hr.) 10 4.60 2.320.00 6.00 6.00 50.4 C_(max) (ng/mL) 10 153 100 17.7 127 360 65.3AUC_(0-24 hr) 10 2210 1650 249 1690 5230 74.6 (hr.*ng/mL) AUC_(0-t) 43390 4120 308 1900 9470 121 (hr.*ng/mL) AUC_(0-∞) 4 3440 4170 328 19309590 121 (hr.*ng/mL) t_(1/2) (hr.) 4 19.7 8.18 12.6 18.7 28.8 41.5 3 160 1 T_(max) (hr.) 10 6.00 3.65 2.00 6.00 12.0 60.9 C_(max) (ng/mL) 10155 125 10.4 113 408 80.5 AUC_(0-24 hr) 10 2500 2050 104 1750 6350 81.8(hr.*ng/mL) 3 16 0 28 T_(max) (hr.) 10 5.60 3.10 0.00 6.00 12.0 55.3C_(max) (ng/mL) 10 286 104 109 309 408 36.3 AUC_(0-24 hr) 10 4590 18901320 4890 7800 41.1 (hr.*ng/mL) AUC_(0-t) 4 7970 2780 4870 8120 1080034.8 (hr.*ng/mL) AUC_(0-∞) 4 8070 2820 4910 8280 10800 35.0 (hr.*ng/mL)t_(1/2) (hr.) 4 25.4 11.9 10.1 27.8 35.8 46.8 4 32 0 1 T_(max) (hr.) 108.60 3.78 2.00 9.00 12.0 43.9 C_(max) (ng/mL) 10 214 90.8 58.2 224 35342.5 AUC_(0-24 hr) 10 3590 1580 999 3640 6590 44.1 (hr.*ng/mL) 4 32 0 28T_(max) (hr.) 10 4.30 3.59 0.00 4.00 12.0 83.5 C_(max) (ng/mL) 10 620309 190 620 1110 49.9 AUC_(0-24 hr) 10 9410 5060 2830 8760 16600 53.7(hr.*ng/mL) AUC_(0-t) 4 24700 13600 8730 24300 41500 54.9 (hr.*ng/mL)AUC0-∞ 4 24800 13600 8810 24400 41700 54.8 (hr.*ng/mL) t_(1/2) (hr.) 448.7 14.8 27.3 53.2 61.1 30.4 5 8 200 1 T_(max) (hr.) 10 9.00 3.16 6.009.00 12.0 35.1 C_(max) (ng/mL) 10 101 56.2 35.2 86.5 182 55.9AUC_(0-24 hr) 10 1470 853 323 1390 2670 58.1 (hr.*ng/mL) 5 8 50 28T_(max) (hr.) 9 6.67 3.61 0.00 6.00 12.0 54.1 C_(max) (ng/mL) 9 152 76.948.0 171 275 50.5 AUC_(0-24 hr) 9 2120 1410 366 2250 4230 66.7(hr.*ng/mL) AUC_(0-t) 3 3010 1990 1040 2970 5010 66.0 (hr.*ng/mL)AUC_(0-∞) 3 3070 2030 1060 3020 5120 66.2 (hr.*ng/mL) t_(1/2) (hr.) 318.0 8.28 8.85 20.3 24.9 45.9 6 16 200 1 T_(max) (hr.) 10 8.40 3.10 6.006.00 12.0 36.9 C_(max) (ng/mL) 10 152 89.7 7.27 171 263 59.1AUC_(0-24 hr) 10 2310 1430 94.4 2470 4280 62.1 (hr.*ng/mL) 6 16 50 28T_(max) (hr.) 10 6.30 4.52 0.00 6.00 12.0 71.8 C_(max) (ng/mL) 10 262170 98.4 213 578 64.8 AUC_(0-24 hr) 10 4390 3270 1480 3340 10800 74.4(hr.*ng/mL) AUC_(0-t) 4 9440 8800 3410 6010 22300 93.2 (hr.*ng/mL)AUC_(0-∞) 4 9590 8860 3610 6080 22600 92.4 (hr.*ng/mL) t_(1/2) (hr.) 452.8 20.5 26.4 57.8 69.4 38.7 Abbreviations: Max = maximum; Min =minimum; N = number of animals; SD = standard deviation. All TKparameters are shown to 3 significant digits.

FIGS. 13A, 13B, 13C and 13D show delivery of various dose levels of AMXT1501 dicaprate in enterically-coated tablets orally to beagle dogs.These figures show approximately dose-proportional increases in plasmalevels of AMXT 1501 at dose levels of 8, 16 and 32 mg/kg/day after Day 1and Day 28. These dose levels were equivalent to 1, 2 and 4 tablets ofAMXT 1501 dicaprate (80 mg AMXT 1501 free base content per tablet) tothese animals, which had an average 10 kg body weight. The PK parametersC_(max) and AUC₀₋₂₄ hr both showed dose-proportionality. These datademonstrate that pharmacological dosing with AMXT 1501 dicaprate inenterically-coated tablets provides a predictable and reliable deliverymethod for this polyamine active pharmaceutical.

Example 10 Pharmaceutical Formulation of AMXT 1501 Dicaprate

Table 22 below shows the composition of the enterically-coated tabletpharmaceutical containing AMXT 1501 dicaprate. Modern pharmaceuticalscommonly contain tableting formulation ingredients such as these toincrease the functionality and oral delivery of the resulting activedrug(s). Descriptions and functions of these common formulationingredients, commonly known as excipients are given below.

TABLE 22 Solid Oral Dosage Composition Function of ConcentrationAmount/Tablet Item No. Ingredient/Component No. Ingredient (% W/W) mg 1AMXT 1501 Dicaprate Active 32.75 131.0 2 Co-processed Starch, NFFiller/Diluent 23.40 93.6 (StarCap 1500) 3 Microcrystalline CelluloseFiller/Diluent 33.98 135.9 NF, PH Eur., JP (Avicel PH102) 4 Ac-Di-SolCroscarmellose Disintegrant 6.90 27.6 Sodium NF, PH. Eur., JP 5Hydrophobic Colloidal Silica Glidant 1.49 3.95 NF, Ph. Eur. (AerosilR972) 6 Magnesium Stearate, NF Lubricant 1.49 3.95 (Hyqual VegetableSource) TOTAL 100 400

Following mixing of the dry ingredients listed above, this powderedformulation is loaded into an appropriate tablet press to produce theuncoated tablets. Quality control testing is performed and content ofactive drug is evaluated (Assay %) together with Content Uniformity (CU)across a sample of uncoated tablets. Coating of the tablets with theenteric-coating is performed using a rotating pan coating apparatus (seeExample 4). AMXT 1501 dicaprate tablets for use as pharmaceuticals arecoated with Opadry™ hydroxyl propylmethyl cellulose (HPMC, Colorcon) asdescribed in Example 4 above.

In general, compressed tablets may be prepared by compressing with asuitable machine, known as a tablet press, after pre-mixing theformulation ingredients in a free-flowing form such as a powder orgranules and mixed with fillers, binders, inert diluents, lubricatingexcipients together with disintegrants to aid dissolution of the tabletsin the gastrointestinal system of the treated subject. The resultingpressed tablets can undergo an additional enteric coating step toprovide a pH-sensitive barrier and enables the coated tablet to stayintact until reaching the higher pH environment of the lowergastrointestinal tract.

Fillers in tablet pharmaceuticals are used to dilute the active agentand to enable precise control of the dose of active drug beingadministered. Common fillers or diluents in common use include lactose,mannitol, xylitol, dextrose, sucrose, sorbital, compressible sugar,microcrystalline cellulose (MCC), powdered cellulose, cornstarch,starch, pregelatinated starch, dextran, calcium carbonate, polyethyleneglycol and hydroxypropyl methyl cellulose.

Disintegrants in tablet pharmaceuticals are used in modernpharmaceutical formulations to aid in the dissociation of excipientsfrom the active drug in the gastrointestinal track of treated subjects.Examples of commonly used disintegrants include calciumcarboxymethylcellulose, providone, crospovidone(polyvinylpolypyrrolidone), methyl cellulose, microcrystallinecellulose, croscarmellose sodium, hydroxypropyl cellulose, starch,pregelatinized starch and sodium alginate.

Lubricants in tablet pharmaceuticals are used to aid processing ofpowder pre-mixed for milling equipment including tablet presses.Examples of lubricants include calcium stearate, glyceryl monostearate,glyceryl palmitostearate, hydrogenated vegetable oil, light mineral oil,magnesium stearate, polyethylene glycol, sodium lauryl sulfate stericacid, and talc.

Glidants in tablet pharmaceutical preparations are used to improve flowof powders and aid in manufacturing using various processing equipmentincluding tablet presses. Glidants in common use include silicondioxide, talc cornstarch, and hydrophobic colloidal silica.

Although any methods and materials similar or equivalent to thosedescribed herein can also be used in the practice or testing of thepresent invention, a limited number of the exemplary methods andmaterials are described herein.

Where a range of values is provided herein, it is understood that eachintervening value, to the tenth of the unit of the lower limit unlessthe context clearly dictates otherwise, between the upper and lowerlimit of that range and any other stated or intervening value in thatstated range is encompassed within the invention. The upper and lowerlimits of these smaller ranges may independently be included in thesmaller ranges is also encompassed within the invention, subject to anyspecifically excluded limit in the stated range. Where the stated rangeincludes one or both of the limits, ranges excluding either or both ofthose included limits are also included in the invention.

For example, any concentration range, percentage range, ratio range, orinteger range provided herein is to be understood to include the valueof any integer within the recited range and, when appropriate, fractionsthereof (such as one tenth and one hundredth of an integer), unlessotherwise indicated. Also, any number range recited herein relating toany physical feature, such as polymer subunits, size or thickness, areto be understood to include any integer within the recited range, unlessotherwise indicated. As used herein, the term “about” means±20% of theindicated range, value, or structure, unless otherwise indicated.

All of the U.S. patents, U.S. patent application publications, U.S.patent applications, foreign patents, foreign patent applications andnon-patent publications referred to in this specification and/or listedin the Application Data Sheet, are incorporated herein by reference, intheir entirety. The following patent documents are incorporated hereinby reference, in their entireties: U.S. Pat. Nos. 7,662,999, 7,432,302,7,411,002, 7,388,112, 7,208,528, 7,199,267, 7,160,923, 6,963,010,6,914,079, 6,872,852, 6,646,149, 6,172,261 and RE43327, and US Pat.Publ. Nos. 2011/256161 and 2006/122279. Such documents may beincorporated by reference for the purpose of describing and disclosing,for example, materials and methodologies described in the publications,which might be used in connection with the presently describedinvention. The publications discussed above and throughout the text areprovided solely for their disclosure prior to the filing date of thepresent application. Nothing herein is to be construed as an admissionthat the inventors are not entitled to antedate any referencedpublication by virtue of prior invention.

In general, in the following claims, the terms used should not beconstrued to limit the claims to the specific embodiments disclosed inthe specification and the claims, but should be construed to include allpossible embodiments along with the full scope of equivalents to whichsuch claims are entitled. Accordingly, the claims are not limited by thedisclosure.

What is claimed is:
 1. A method of treating a solid tumor cancer,comprising administering to a subject in need thereof a therapeuticallyeffective amount of a salt of formula AMXT 1501:(capric acid)₂, whereinAMXT 1501 has formula:

wherein the salt is administered in conjunction withdifluoromethylornithine (DFMO), or a pharmaceutically acceptable saltthereof.
 2. The method of claim 1, wherein the salt is administered in asolid dosage form to the subject.
 3. The method of claim 1, wherein thesalt has chemical structure:


4. The method of claim 1, comprising administering to the subject atherapeutically effective amount of a pharmaceutical compositioncomprising the salt of formula AMXT 1501:(capric acid)₂ and apharmaceutically acceptable inert component.
 5. The method of claim 4,wherein the pharmaceutical composition is in a solid oral dosage form.6. The method of claim 5, wherein the solid oral dosage form isenterically coated.
 7. The method of claim 1, further comprisingadministering DFMO, or a pharmaceutically acceptable salt thereof, tothe subject.
 8. The method of claim 1, wherein the subject is a human.9. The method of claim 1, wherein from about 0.05 to 100 mg/kg per dayof the salt is administered to the subject.
 10. The method of claim 9,wherein from about 5 to 50 mg/kg per day of the salt is administered tothe subject.
 11. The method of claim 1, wherein the salt is administeredto the subject once or twice per day.
 12. The method of claim 1, whereinthe solid tumor cancer is breast cancer, prostate cancer, colon canceror lung cancer.
 13. The method of claim 1, wherein the solid tumorcancer is breast cancer or colon cancer.
 14. The method of claim 1,wherein the solid tumor cancer is neuroblastoma, pancreatic cancer,bladder cancer, melanoma, skin cancer, kidney cancer, head and neckcancer, ovarian cancer or thyroid cancer.
 15. The method of claim 1,wherein the solid tumor cancer is neuroblastoma, pancreatic cancer,melanoma, skin cancer or head and neck cancer.
 16. The method of claim1, wherein the solid tumor cancer is glioblastoma.